Quite honestly, unless you’re a worldwide top level professional arena player, or are getting payed to do speedruns I highly doubt it matters, and even then. I’m one to notice lag very quickly and my MX Revolution is hardly noticeable in that regard - and by “hardly” I mean “not at all.” Maybe the lower end cordlesses still have this issue, but I can quite easily score in the top 3 in FPS games (which are way more reaction intensive) with this thing.
Besides, mastering clicking will only get you so far, there’s a reason rudimentary combat efficiency is measured in keys pressed and not times clicked (at least it is in WCIII and Starcraft, I’ve seen the terminology applied to WoW, but it may not be as widespread in MMOs).
I used to be a clicker, there really is no comparison, especially if you play a class with talents that reduce global cooldown after certain skills (I think DK has one off-hand not sure about other classes), there’s barely enough time to reach certain skills in the GC, much less half that. If you can’t get into the swing of hotkeying, I’d actually recommend taking a 1-2 week break from WoW, which is usually enough to flush some of your habits enough that you can replace them.
Now, to almost completely contradict what I just said, I’d take “attack” off the hotbar completely, right clicking accomplishes the same task just as easily while you’re selecting the mob (tab+targeting is very inefficient, and often leads to mistargets at best and wipes from pulling adds at worst), and especially as a warrior there’s rarely a time in combat that you’re NOT auto-attacking (abilities excluded).
I’m obviously not a warrior, so take that with a grain of salt, but generally what I said seems to be the generally accepted community principles.
However, this is also the “play your best” stuff, I was still a good warlock when I clicked, and I was good enough to be a top-tier instance pick and 4 man all but one boss in (post-nerf) Scholo with two locks, a rogue, and a shadowformed priest with only the priest at 60 (though I’ve never raided for various reasons) in guilds and among friends, so the real answer to any of these questions is “play however you damn well please,” all the stuff I said is merely small ways to improve your game. I was good, I just got better, and if there’s one place it’s noticeable, it’s leveling. With faster reactions and more bindings you survive longer and kill faster which are integral to the two most important aspects of leveling (get XP and don’t die).
This sentence is just to end my post, because that last paragraph was originally a closing sentence and I kept needlessly expanding on it so I need something completely different to stop typing.