I had no idea so many people felt this way about mechanics. Hell, pretty much everyone reacted
negatively to 02's. Mendez, what have you wrought???
I'd like to just reiterate my point of view; special mechanics are NOT necessarily bad, just like they're not necessarily good. Some are not practical, true, and others are needlessly complicated (Grimer is guilty as charged), but they add some spice to the moveset and spruce up attacks which would otherwise be dull. That doesn't mean tack them on because you want to have one, but implement one if:
A) The character needs it to be interesting.
B) It suits the character to a T.
C) You already thought up a simple YET interesting one that could fit.
For an (off the top of my head, I'm bound to be biased) example of A, take Electrode. How boring would that have been without some sort of mechanic to make the, well, spinning attacks more interesting? A secondary example could be Peter Pan; the character doesn't really do much other than swing around his dagger, the flying mechanic really let him take off.
A recent example of B would be Shadow Beast; that mechanic is absolutely perfect for the character and makes the whole moveset feel more genuine.
And for an example of C... since I can't speak for anyone else, take my Headless Horseman. Tossing his own head around like that may not be entirely specific to character. He has plenty of capacity for interesting attacks without it. But I put it in anyway, because it's a good idea. Yes?
Anyway, that's how I look at it. Variety is the spice of life, and a unique mechanic WILL help your cause. In the end, we're not game designers (I'm not, anyway), and 95% of our ideas would need severe tweaking to be implemented. And what's wrong with that? This is a theoretical exercise, we're allowed to push the boundaries of what's possible in Smash. The day Sakurai asks me to actually design a character for him, I'll lose the special mechanics and give him Jafar or something. Until then, I'll opt for creativity every time.
Just my... long two cents.