Braukaiser gave a presentation on this exact topic at last year's Australian home brewing conference and yes, it can work.
The reason for doing it was to create even more fermentable wort for particularly dry beers.
I can't remember exactly how he does it but I'm pretty sure it was via a reverse decoction of some sort. I've been meaning to find his notes anyway, so I'll post the link if I find it.
From very hazy memory, the idea was to mash in low, rest for a short while, remove an amount of the enzyme-rich liquid, and keep it aside as you raise the temp of the thick part of the mash. After the thick mash has rested at the higher temp, add the cooler, thin mash back in to drop the temperature.
I hope to try something like it on a beer with lots of complex malts that I also want to finish v dry (eg altbier).

BN Army // 13th Mountain Division 