Valve job with head gasket replacement?

When I was in the business, it was std practice to mill the gasket surface of the head when doing a head gasket replacement. On the old V8s you can do this with the head assembled, and clean it with a reasonable amount of certainty that you could get all the chips out. But as part of the inspection it's not hard to see if there's a sealing problem with a valve. And the test is even easier... Flip the head chamber side up, and fill the chamber with water. If it leaks past, closer inspection is needed (as in remove the valve. Overhead cam heads you couldn't - and if it's all coming apart anyway, time for a valve job.