The Fender Hot Rod Deluxe is a good amp although I prefer the 410 to the 212 because it is brighter. Maybe the guitar or the amp is a lemon, I dunno. Sometimes an amp and a guitar just don't agree with one another.
Tubescreamer adds a lot of tone if used properly although like any other piece of equipment, it can be a disaster in the wrong hands. You can try not letting the guy put his guitar on 10 but if he's the kind of person who doesn't listen for tone and only hears volume, he's probably going to put the guitar on 10 no matter what you say. But agree with what other people are saying - I get my best guitar tones on my strat around 7 and on my Rickenbacker around 6.