Here's what bugs me about the current approach to short rests: It's not at all clear to me, in terms of the game world, why you shouldn't be able to take two short rests in a row. Let's imagine two situations, assuming a fighter who has already used her second wind once:
SCENARIO #1: Our fighter gets in a fight and takes seven damage, putting her at 5. She takes a short rest, regains her second wind, and uses it to gain three hit points, putting her at 8.
Then she gets in another fight, but doesn't get hit at all. She takes another short rest, uses second wind again, and regains four, bringing her back up to full.
SCENARIO #2: Exactly the same as above, but there is no second fight. As a result, the fighter is unable to benefit from the second short rest and remains at 8 hit points.
Why does this make sense? Given the exact same amount of resting (two short rests' worth), why is it that you become more rested if there's a fight in the middle?