The idea is pretty simple: bittering due to alpha acid isomerization is a function of boil time and quantity of bittering hops. Hence, it's quoted that from an alpha acid standpoint, a 15 minute boil with twice the quantity of bittering hops is fairly equivalent to a 60-minute hop addition.
I'm a bit lazy, and I'd rather not steam up the house any more than I need to, so a shorter boil time definitely has an appeal. Plus, it seems like more of the nice aromatics would be retained, which sounds like a win-win.
Doing a little research, I'm noticing that I see a decent amount of 15-minute American pale ale recipes popping up, almost at the exclusion of other, more malt-forward styles. That's got me curious:
Is there a benefit to a full-length boil, other than saving a few bucks on hops? Is there something that happens on the malt side that takes time?