From a recent BYO wizard segment:
http://***********/mrwizard/1593.html
I might start doing this. It makes me want to smack my head and say "Why didn't I ever think of that???!!!??"
.....In fact many pub brewers mash-in, take a short breather and begin wort collection. My old professor from University of California-Davis is the one who started pushing this idea. The reason it works is that there is no mash-off step and as long as the wort collected in the kettle is not prematurely heated, conversion of starchy worts continues in the kettle during wort collection and the amylases in the mash are active during almost the entirety of sparging. Brewers doing this use much shorter mash times.
http://***********/mrwizard/1593.html
I might start doing this. It makes me want to smack my head and say "Why didn't I ever think of that???!!!??"