inthemtns: I don't know what Jeremy Jones' education is, but he often has guides forecasting and advising him.
OP: your question is actually always a toughy. I'd echo some of what HMS said. To get more to your particular point, how do you judge that steeper slope that you cannot get onto for a pit? That 45 or 50 deg couloir or just over a cornice? There is some degree of guestimation involved. This is where HMS's points come in. If you are aware of the local snowpack's structure on that aspect and elevation as a generalized notion (spacial variability between and within slopes always applies). Add in your recent weather history and observe local terrain features and snow surface features to see how heat and wind have been playing. Form a range of possibilities in your mind of what the snowpack may look like. If you can find a representative slope to confirm this hypothesis with, that's great. IF YOU CAN'T you really have to decide how certain you are that your "nowcast" is right and whether you are willing to risk being wrong.
What can you say about the risk of the steeper line versus a less steep line? We are all familiar with this graph:
But let us consider it more deeply as it is misleading at first glance:
1. There are just plain more slopes that are less steep, especially in certain climates.
2. The distribution of frequency by bed surface angle varies by snow climate and avalanche type (slab versus wet, maritime versus continental).
3. The influences on these steeper slopes varies by area. For example, in Colorado, most of the steepest lines are in couloirs and are subject to wind sheltering, cross loading, solar shading, and direct/indirect solar affects like horizontal TG and rapid melting much more than open faces. (obviously this affects other skiing safety factors in addition to avalanche danger)
4. Additionally, many avalanches still occur on these steeper slopes, but they are more prone to naturals during a storm cycle because of our friend gravity.
More to the point of #4, particularly gravity, what the graph is trying to say is that slope angles in a certain are more prone, other variable aside, to accumulation significant amounts of snow before breaking mechanical equilibrium (avalanching) versus constantly sloughing (steeper) or not having strength overcome by strain (lower angles).
So could a 50 deg slope be safer avalanche wise than a 40 deg slope? The answer is sometimes in some ways. You have to figure it out case by case.
Lastly, you must consider whether your line, which inevitably decreases in pitch at some point, will present you with more avalanche danger as you descend onto lower angle areas that may be holding more "pregnant" snow.
In the most extreme cases and with proper training and experience, one could do a belayed analysis of an otherwise inexaminable slope... but that is for the rarer circumstance.
I won't get to specific for you because I don't know you and I don't really know Tahoeland.
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