Heating mash before lautering?

Hi Folks,
Quick question, are you supposed to heat your mash to sparge temps before lautering or do you lauter at the proper mash temp and then sparge with your 170 degree water? I just noticed a video online of someone heating the mash to 170, lautering and then running the 170 degree sparge water over as well. Never done it that way.
What do you folks do?
Thanks for any input.
HAPPY FRIGGIN' FRIDAY!!!:rockin:

its called a mash-out. The high temp will end the enzyme activity and achieving it with a bunch of water will thin out the mash and allow an easier lauter for tricky grains like oats. Not really necessary if you're not having stuck sparge issues and brewing normal beers. Skipping this step you end up just using more sparge water and I think the larger amount of hot sparge water also stops enzyme activity but don't quote me on that.

If you can raise the temp to 170F, the liquid will flow better. I mash in a pot, so I raise the temp to 170F by turning on my burner and then add sparge water at 170F or higher temp.