User blog comment:Zilverdael/Seperate itemsets and why they are good/@comment-5035765-20140614051708

yeeeeeeah no

this makes it WAAAAAAY harder to counterbuild or adapt your build when things go wrong. Like tanks, for example, build different defenses depending on the damages the opponents do (well, the ones with half a brain do at least... i guess that eliminates a lot of soloq players, LOL)

also, it enforces meta way hard, which is something Riot is not wanting to do at all (and before you say anything about Team Builder, it actually does the opposite.  It's the players enforcing the meta there).

And what about champs with many viable builds? Jax, Kayle, Eve, and Warwick (examples off the top of my head) would be way limited in build more than they already are by Riot's seeming hate of Hybrids...