| Kuroimaken |
Speaking as someone whose min/maxing has been forcibly "toned down" for a number of years, among other reasons because the DM felt as if he knew more about the game than I did, I find the Tier system to be fairly good as well as reasonably accurate for its purpose. Thanks to multiclassing and PrCs, there is no way to accurately gauge a class' power level in terms of playing style 100% of the time.
BUT! When one comes across that minuscule iota of a fact, the initial feeling is that multiclassing must go. Some people consider that multiclassing AT ALL is the source of all brokenness in D&D. They're not entirely wrong - flexibility is what enables someone to make the most varied/specialized characters all - but it's not the single truth. They then move to the next step - Core-only games. In my group, that step was actually the banning of ToB + Psionics as well as anything with "Compendium" in its name (yes, even the Rules Compendium). They're still wrong, because then the discrepancies in power spike even further; and then they move to the final step in the stupidity scale, which is moving to 4e, where everyone is EXACTLY. THE. DAMN. SAME. and the difference between being a Fighter or a Wizard only goes as far as determining what kind of stick you beat people up with.
At least with the Tier system, the differences are recognized, and the DM can actually do something about it, rather than twiddle his thumbs as he watches the Warmage suck when he's not a Rainbow Servant.
Also, those who advocate that working with the Tier System AT ALL equates to throwing RP out of the window can all go play 4E for all I care. To quote two of my favorite lines about D&D on the internet (one of which, I believe, is by Tempest Stormwind, whom despite his shortcomings - we all have them - participated extensively in the min/max versus RP issue):
"You can't roleplay when you're dead." (My amendment: "unless your DM lets you play a ghost.")
"It's futile to argue about how the mechanics are messing with your role-play in a game that is largely about combat."
Above all, remember. The Tiers are, despite all logical analysis involved, largely opinion. Opinions can be wrong - including that of those who hate the system - and confusing them with fact is very easy.
However, their purpose being analysis, to barge into a discussion about it only to express your distaste for them is as much a waste of time as watching grass grow.