jetwildcat, what you're saying is incorrect. I played HS basketball, my best friend is a college coach, my dad coached in HS for a number of years, etc.
If you're guarding your man that closely, let's say you're face guarding a shooter, you're bound to get burnt on the boxout because you don't have enough room to check him and get your *** into him (that is, if he's going after the offensive rebound very hard, which most people that you're face guarding/no help probably won't be).
If you're letting a team chuck it, you're going to have time to set up and beat your man to a spot on the boxout.
Now, practically speaking, the fouling thing doesn't make much sense. You'd get a helluva a lot more hand checks if you were playing everyone on the perimeter tight. You'd get less fouls on drives (that get inside the lane) or rebounds of course.