I can sure agree an argument could be made for Tyler winning, and obviously he came close. He was also admittedly integral in strategy, planning, and execution. However, Tyler got "blood on his hands" and made several top 2 deals he obviously could not (or had no intention of) honoring and made other "broken" promises.
This is why I say KC played a brilliant game. She was able to play such a stellar social game, one of the best I have ever seen on Big Brother. She was able to nominate and eliminate people from the house without getting one spot of blood on her hands. She was a fierce competitor, a veto killer, and won when it count. more than all of that, she was able to do this without having to lie and break promises. She even was true to her word in the end taking Tyler to the end instead of JC.. even though JC might have been easier to beat and even though Tyler just broke his promise to her about dropping in round 1 of the final to let her have it. She also (true to her word) kept Tyler over Angela, who would have been much easier to beat heads up in the final two.