In my opinion, tagging a player helps only if you play with these players too often. Tagging players you just played with a few times, might do you more harm than good, because you cant judge a player if you just saw him play a few times.
If you tagged him as a bluffer just because you saw him bluff a few times, then you come across him and he pushed with a monster card like AA or KK, and you have an ace or a low pair, and your tag says hes a bluffer, the next thing you'd do is call.
Before you know it you are already in a deep hole because of that tag. :P
__________________
|