Thanks for the tips and tricks. :]

You need MR per level, not flat MR on AD carries since you don't really face mages till later in the game

I am going to upvote this cause of the depth you go into, and will probably go into it even further as the guide progress, however, i have a few oppinions.
Imo, the bloodthirster is a little late, you should atleast get a vamp sceptre after the trinity force, 'cause without any sort of lifesteal part from the 6% from dorans + masteries, you won't survive for long in a trade, there's a big difference between 6% and 16%.
I also think that you underestimate Phantom Dancer on Corki, I usually build him like this: Boots + 3 pots, 2x dorans blades, rank 2 boots, blood thirster (get it to 40 stacks during laning phase), IE, PD, Black Cleaver (I find it isnt that useful until late game, as you're not to focus the tanks anyway) and end the build with a Guardian Angel. Most of the time, spamming your ult/Q for the Tri Force proc simply just isnt worth it, I find I deal more damage just auto attacking with E active.

Keep it up though!

i was first voter... and first view... HA

Thanks a lot! Come check on it later as im always working on it!

A very detailed guide, this gets my vote. :D