Good game management does not consist of whacking a coach w/ 2 T's for the statement that was posted earlier. Doing that will certainly get you in trouble (probably from your assignor). Good game management consists of calling fouls that make sense in a 20pt blow-out game. You can't make stuff up - the contact has to be there and it has to be relatively close to the amount of contact that was whistled a foul previously. If it's a solid foul, you've got to call it.
If something is within the "grey area", than I would certainly give the benefit of the doubt to the losing team. Remember it's "grey area" stuff - a contested ball batted OOB's; 3 sec./5 sec. calls, contact around the basket, etc. Very few things are "black and white" during the game - there's lots of "grey", so use your judgement.
I'm sure there's lots of posters who disagree - so "fire away".....