[QUOTEk]Curiously enough, the core rules actually offer a mechanism for these partial successes.[/QUOTE]
That's true, but I don't think it's quite what I'm looking for. I would have to find some way to ensure that no such check could be failed by 5 or more. The problem is that falling / uh... falling... / drowning just isn't much fun. Swim is probably the least troublesome of the lot, as you can manage several failures and still be "in the race" to a lesser or greater degree.
I suppose that one option for Climb checks would be to make them opposed checks. At least that would work in cases where you where racing someone. And it is pretty rare, at least at level 4 (or so) and above, to be climbing where a spill would mean instant death. (I guess I'm perhaps a bit more gunshy, personally, of Climb than I'd like to be... I had a tendency in AD&D to play Thieves, and one DM in particular liked to throw tons of 20' deep open pits at us... Climb up and down enough of those and you'll fall a bit...)
Jump is more problematic. I think one possibility for encouraging Jump (and Climb) checks would be to have the DCs more obvious to the players. Possibly record them on the table somehow (easy on a battlemat, since I've switched to Dungeon Tiles I'm not sure...). However, there are going to be far more cases where the PCs are going to be jumping across drops that could cause serious problems. Not only is there falling damage, but it also splits the party up, quite possibly in combat.
I'll admit I'm kind of lazy about taking 10 / taking 20. If I think something is within reason I usually just decide how much time it should take instead of assigning a normal DC (assuming no distractions, etc). That might be part of the issue, as I'm not sure players really "feel it" as much if they don't get to roll the dice, but at the same time they tend to not value anything from non-combat play as much as they do from stuff that involves a fight...
Ideally I'd like an option that will let the players roll dice during combat, give them a meaningful bonus for success (and probably a noticeable, but not crippling, penalty for failing), allow them to get positive circumstance modifiers for good thinking / planning, not slow down the game too much, encourage cool descriptions / action scenes, and that the players will voluntarily attempt, rather than having to force it on them.
(Because I'm pretty sure that "There's a ten-foot wide, twenty-foot deep pit in the corridor. You need to either jump across or one of the Thieves will have to climb down and then back up so you can get your portable rope-bridge set up..." wasn't really all that cool back in 1979...

Sorry, Jeffy!!!

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