Feel free to disagree, point out things I've missed, etc.
tl;dr:
YDS is too ingrained to replace, and it has objective value. Borrowing some modifiers from climbers for Class 5 and applying them to the lower levels can help. 2X is sketchier than 3- G, etc for describing sections of a route.
At the end of the day anything complicated needs some narrative, so trying to come up with some perfect grading system seems impossible.
Some general thoughts of mine on the issue:
- Trying to replace the YDS seems somewhat futile, it's commonly used and (somewhat) well understood. Taking existing climbing ratings and completely changing their context, or making up a new alphanumeric system will add more complexity than reduce.
- That said YDS system isn't designed for backpacking, as Class 2 is too broad, and Class 4+ is focused on climbing.
- The YDS at least tries to be objective (if wiggly) - rating things solely on "feel" doesn't seem like a good approach to me.
- Multiple people find utility in the distinction between class 2 and 3 as shown in the XC passes entries for Dumbbell & Valor etc. Some don't, but there's a sizeable group of people that draw a hard line on simple "climbing".
- Using the YDS system with Class 5 climbing modifiers applied to Class 2/3 seems reasonable to get some more granularity.
- Any pass worth spending a lot of time on is bound to have different sections where the YDS system + modifiers is useful, vs trying to have one holistic rating.
- Trying to cover every use case with a modifier seems impossible - ok so we split Class 2 into loose and stable. I really enjoy dropping over steep loose if it's all deep sand - but if it's a chute of large talus mixed in with loose sand, or ball bearings on top of rocks I don't. Wobbly talus can be fine, talus/scree that self-brakes is fine, talus that can slide for 30ft or more isn't fine. Do we want to decipher 2-2ST30+MSPG-13 or something?
- Sticking with climbing conventions and listing a pass solely by the most complex section doesn't seem right. If a pass is 99.9% Class 2 like Valor Pass it's nice to know there's a short Class 3 bit at the top, but it's a mixed Class 2/3 pass IMO.
- Slope angle shading overlays on maps (CalTopo, Gaia, etc) make it trivial to find a general angle of a pass or col.
- Good narrative descriptions & photos (or notated maps) will always be necessary for anything of complexity anyways!
According to Secor (he goes into more detail, this is his initial brief introduction, it's well worth owning your own copy, the third edition is the latest):
Class 1 is walking.
Class 2 is defined here as difficult cross-country travel. In the High Sierra this is usually talus hopping, which requires the occasional use of hands for balance.
Class 3 is where the climbing begins. Hands and feet are used not just for balance, but to hang onto the rock. Steep or large talus can be rated as class 3.
Class 4 is on steep rock, with smaller holds, and a lot of exposure.
Realistically we're only concerned with 1-4 with a pack on.Class 5 is steep and difficult rock climbing, involving the use of protection placed between the leader and the belayer. I differentiate class 4 from class 5 by the hand- and footholds. Class 5 requires obscure holds[...]
Another way of differentiating between classes (which is intuitive if overly simple and lacking in nuance) is the points of contact system, counting rope as a point of contact (I didn't come up with it and don't think it's better than Secor, but it's simple).
C1 = feet
C2 = feet + 1 hand [or trekking poles extended/contracted, used on steep or loose terrain]
C3 = feet + 2 hands
C4 = feet + 2 hands + rope (recommended)
C5 = feet + 2 hands + rope + elaborate means of protection
Overcoming flaws in the YDS:
Exposure
I personally borrow the X modifier from climbing and apply it to Class 2-3. This would be an example of what I'd call 2X on Ursula Pass (a bit warped due to 13mm lens): download/file.php?id=34462&mode=view
It's not standard, but it's fairly easy to understand and makes for more sense than "everything class 4 is exposed".
Adapting the climbing exposure/danger rating system on top of YDS makes sense to me (vs replacing it) though obviously "protection" isn't really relevant and G and PG would need to be modified.
G = no real risk. could sprain an ankle but that can happen in the parking lot.
PG = loose or rough terrain where you might get banged up, but unlikely any more than that.
R = unchanged, risk of serious injury if you fall
X = unchanged, risk of death if you fall
The wide range of Class 2 terrain
I will sometimes add a + or - symbol based on if I feel something is trivial or advanced for it's class (again borrowed from climbing). A super chonky short bit of class 3 (getting over the easy chockstone near the top of the Blackcap side of Finger Col) probably won't deter anyone that's gotten that far, but it isn't class 2... but the Class 2 there is pretty steep and can get exposed and some routefinding sensibility is key. I'd put it at 2+ with a few short moves of 3- but usually do that more in casual conversation vs the top of a write up where I just explain things in narrative form. While the YDS is pretty objective, these are obviously subjective, but are still useful.
I'll usually just break this into words as it's more descriptive anyways.
Vernon Pass - CLASS/DIFFICULTY: Advanced class 2. We added in some optional easy class 3 (slab vs semi-stable talus).
North Col - CLASS/DIFFICULTY: Class 2, with some stable ledgey Class 3 the top that one can mostly avoid.
I'm not sure just saying the south side of Junction Pass is loose would paint the picture, and my subjective experience was far different from my partner's - which I tried to capture in my writeup of the pass. If there's ambiguity of interpretation I'll try and look at things from different possible perspectives.
A moderately steep slope that had some rocks but was fairly stable was be a 2-. I usually say easy class 2.
Talus that's nicely sized for moving and is stable to wobbly would be 2. I just say class 2.
Unstable talus on a slope, or a loose slope with talus mixed in, etc would be 2+. I'll usually say advanced class 2.
Breakpoints / ambiguity between Classes
1 and 2
I personally don't agree that all trail is class 1 and all off-trail is class 2, and that seems to be the consensus. There are plenty of flat slabs, gentle walks, and open spaces that don't have a trail but are essentially just "walking". Talus, scree, etc pose obvious "you aren't just walking yet" terrain. I'd also include density of underbrush and other obstacles - lots of deadfall on a steep traverse would count for me. I do actually have a little theodolite app that measures slope and can lay it over a photo, but I view it as a novelty vs a hard "oh this is over 30deg so it's class 2". Differences of opinion at this level are likely to be somewhat trivial.
A lot of abandoned trails fall into Class 2 at times as they get overgrown, covered by a slide, etc.
2 and 3
In general I find it useful, as 2 and 3 are pretty objective, though they can vary for people and it's useful to get a feel if one is off course (huh this was supposed to be Class 2, I must have taken a wrong turn). Long sections of Class 2 with an occasional move or two of Class 3 can blur, but the "hand for balance" vs "hands to hang onto the rock" via Secor is a great way of looking at it IMO. If you're pulling yourself up with both hands it's Class 3, even if it's a simple single move mantling on top of something.
Someone slid into my DM's a while back with questions on the Class 3 bit of Valor Pass. For the route we did there were two bits that would fall under that category.
The first I said was somewhat ambiguous Class 2/3 and could vary based on someone's experience, body size, etc. I'd say this is technically Class 3, but someone experienced just going up it might just think of it as Class 2. I don't think there's a major issue if stuff like this is confused, when in doubt adding an easy/advanced +/- modifier
download/file.php?id=35134&mode=view
The second bit is just solid Class 3. We didn't find it challenging with packs on, but it's not something that anyone could mistake for Class 2!
download/file.php?id=36399&mode=view
Class 4
This definition really does need to be adjusted for backpackers by dropping exposure. There are times where I'm doing something that's more difficult than Class 3, but I'm not exposed. I've carried my pack up some 10-20ft bits of Class 4, gone up a chimney, done an akwward wiggle off a ledge etc. That said sustained Class 4 generally isn't done with a pack unless someone is a proper climber.
I tend to ignore the exposure side of this and just say "there's an unexposed xft section of Class 4". There's a drop from Mattie Lake into the area below Glen Aulin that I've done twice that has a short unexposed set of Class 4 moves off of a ledge - I don't find it worth re-routing into a bunch of bushes to avoid, but that's how I'd describe it to someone as it's not just Class 3.
Impact of Trekking Poles
IMO poles count as a point on contact on steep terrain, similar to using a hand for balance if they're nearly often load bearing or used to keep balance when a foot slips out etc. An indicator for me that I'm probably not on Class 1 terrain anymore is if I'm going up something at -10cm of my normal, or down at +15-20cm. There's a lot of Class 2 I don't use my hands to steady myself on because I have poles, but I would have at points if I almost certainly would have at one point or another.
Obviously using poles on true Class 1 (walking to Soda Springs in Tuolumne) doesn't magically turn it into Class 2 (similar to how straightforward Class 2 with a drop on one side shouldn't be considered Class 4 because it's exposed).
Threading the Needle vs CYOA
A lot of passes are class 2/3 and as long as you don't cliff out in a spectacular self-imposed terrible judgement call your experience won't be too much different from anyone else's. Gain the ridge and drop is really enough for some passes!
Others like Finger Col, Cirque, etc have a section or two where there's a meaningful navigation choice that bumps you up a class or two - I try to emphasize those when writing about a pass - vs sharing "this was my experience, but you don't need to try and follow in my footsteps". If someone will end up on Class 4 vs Class 2 that's something vs emphasizing vs slightly varying difficulties of Class 2/3 with no real consequence. I prefer chunky 3 over loose 2, others feel otherwise, etc.
