Sorry that this is just a link, but this forum doesn't have spoilers and the thread would fill the entire page without spoiler tags.
The thread is about what mid laners don't commonly max skills that make their creep clear optimal. I list what they usually max, what they can max for better creep clear, and what they can max for better creep clear, then I compare their numbers, and then I finally judge whether it is worth it or not.
I feel that a few mid laners are underrated because people max the wrong skills. A good example is annie, so here is an example.
Commonly maxed skill: Q
Alternate maxed skill: W
Pros: More Creep Clear
Cons: Less DPS
-Slightly harder to charge your stun
Verdict: Worth it.
Annie is all about burst, and this gives you more burst. Sometimes you need a second Q to finish off your enemy laner after a combo, but usually a level 1/2 Q will be enough in that case. You also get great creep clear, so you can gank other lanes with that AOE stun. It also makes it much easier to clear wraiths. The only real downside is that you have to wait for minions to be really low before you can Q it for a stack on your passive.
The thread does the same thing for Anivia, Cassiopea, Kassadin, leblanc, and Swain.