I don't want to beat the subject down to the ground, but a couple of other thoughts:
First off, those of you speaking up to defend the TP system are likely not the ones with the "TP narcissim" problem. The ones causing the problems are (likely) too embarrassed to join in on this thread - which is fine. So far, all the posts in defense of TPs are (accurately) describing the benefits of the TP system. The "attaboys" aren't a bad thing. But that's separate from the issue of other posters who are abusing the TP system. That's where the balancing comes in. It appears from the comments (especially from the staff), that most people believe the pros outweigh the cons. Fine, I guess. Those of us that disagree will live with it.
I will say one last thing, though, that's always puzzled me about TPs. If the TP is given anonymously, then there's no way to build any camaraderie from it. In fact, if you're not on the blog 24/7, you may not even know which post of yours caused you to get a TP. So, in the anonymous case, the feedback isn't really useful for anything other than gaining bragging rights for a high TP count.
On the other hand, TPs are very frequently given non-anonymously. When this happens, you know who gave you the TP (builds camaraderie) and you know exactly which post caused the TP (helps reinforce quality posts). But in those cases, the TPs are redundant because you're actually posting in the thread something like, "I agree" or "Interesting point - TP for you." If people are making actual posts to say "TP for you," why keep a running tally of them on the side if nobody cares about the number anyway? If the reason you like TPs is because you like having a mechanism to say "attaboy," you've already got one (and probably already use it) - just quote the post you like and say "TP."
EDIT: I was just thinking how I enjoy just as much as the next guy when someone comments on one my posts and gives me some positive feedback. Positive karma is a good thing. But I never find myself gaining anything when I see that my TP count is higher...