Talking with a friend who's about to TR her 20 pure kensei into yet another fighter. She asked me for help, and I'm no expert at all, so better post it here and check your opinions on the matter. She wants to stay pure fighter again to get the capstone. I said to her that, being me the one building the fighter, would forget the capstone and instead get 2 levels of rogue, since I do like evasion (Also, grants the possibility to get Hamstring, which is a nice feat to have on raid bosses). But that was me talking about my preferences. Getting to real facts: Is the fighter capstone worth it? Would she lose so much by splashing those 2 levels?

Thanks for your answers.