Here are the last two sessions I've run, neither of which worked well with the SR/LR mechanic:
I might have been able to push them toward taking a short rest in the second case, but how do you characterize it without making it sound completely implausible? Sure, you've alerted numerous enemies, but you feel confident they're all dead? Sure, there's a big bad guy, but he doesn't really care what goes on in his cave? Yeah, you can take a lunch break, what are the odds that anyone in the cave complex will do anything that involves moving to a room containing either you or a bunch of dead guys you've left behind?
A five-minute rest would be easier to squeeze in, but easier to abuse as well.
- Out of the Abyss: full of long travel stretches with few encounters per day (even, sometimes, days per encounter). As a player, there's no reason not to throw your all at a travel encounter, because in the rare case you get another on the same day, you can generally squeak through it with whatever you have left. Certainly you could short rest after every one to be on the safe side. I suppose I could throw in a really pumped up second encounter to put a scare into them, but I can't reasonably do it often enough that they feel a strong need to conserve resources during travel.
- A scenario I was handed involving chasing minor enemies into their underground cave with the goal of confronting the major enemy hiding in the back room. There were 5-ish small encounters before the big one. But the players didn't rest. Partly I think they were excited to reach the goal, and partly it didn't seem sensible to just stop in the middle of cave-delving when any of the prior encounters could have potentially alerted the major enemy. Hard to know if one guy in hiding snuck off to warn him, or if he had one spell set to warn of intruders or whatever.
I might have been able to push them toward taking a short rest in the second case, but how do you characterize it without making it sound completely implausible? Sure, you've alerted numerous enemies, but you feel confident they're all dead? Sure, there's a big bad guy, but he doesn't really care what goes on in his cave? Yeah, you can take a lunch break, what are the odds that anyone in the cave complex will do anything that involves moving to a room containing either you or a bunch of dead guys you've left behind?
A five-minute rest would be easier to squeeze in, but easier to abuse as well.