I'm confused. Yes, there's all sorts of feinting and parrying and such in real sword fighting, but that's not part of D&D. All that stuff is abstracted away in the game. The decisions you actually make are the ones I described: choosing which square to stand in, choosing which target to attack, weighing the trade-off between provoking an opportunity attack and moving yourself to a better position, choosing which spell to cast, etc.
Well, you'd be wrong. I've thought about it a LOT. (Also, I'd love to hear your thinking on these topics, but I find conjectures about my own to be unnecessary.)
I could offer lots of examples that are somewhat analogous to the feinting/parrying/etc. examples in combat, but...again...that's not what is modeled by most RPGs (at least in D&D derived RPGs, which is the forum we're in).
We could lay out...or create random tables for, or even write software to automatically generate...climbing "routes" that required genuine decision points. An example of a decision point could be the choice between grabbing an easy hold that looks like it might be loose, or dynoing past it for the ledge, but risk missing. Or between a friction move requiring finesse or a brute force one-handed pull-up. Or a resource decision: do I put in a piton now, or save it for later when I might need it more?
But all of those are still an individual making decisions, and the cliff is not responding to those decisions. It would still miss what makes combat engaging in RPGs: a team of people all contributing to the group effort, opponents making their own decisions, all those dice rolls smoothing out the curve to mitigate lucky and unlucky rolls, and the situation evolving turn-by-turn because of those decisions and their outcomes.
So, sure, it could be a clever mini-game within the game, but more like a board game and not like an RPG.