Does anyone play test the champions after changes are made?

So I stopped played after a long while, came back, played some games, everything seemed fine. Some champions are still never picked, and some are still hideously overpowered, which I assumed would be the case as Riot balances as well as a lopsided fat man sitting on a chair tipped back over a cliff.

Though there are champions that are heinously overpowered as far as damage numbers, Cho'Gath not only still has his execute, but the health stacks go above a set 10? Who in the hell thought that was a balance? His ult, which not only does ludicrous amounts of damage, can now give him more health than a Warmogs, Spirit Visage, and Sunfire Cape combined. Last game he had 15 stacks, and now since he cannot lose them, he had 2400 health.

Seriously, play test your game, it is broken, and there are other options in the world, so you may want to do it sooner rather than later or people will leave for greener pastures.