LFR doesn't make people learn their class. This game is a group game and it requires you to do nothing to get a group but afk for a que to pop. The best way to do an encoutner in LFR is to stand in everything, ignore every mechanic except the FEW that acutally can hurt or kill you (death beam on Durumu is the first one i can think of). It's no work for rewards. That's just not what a game should be. You should have to put in SOME effort to get any rewards.
Flex raiding is actually DECENT. It makes you at least put some effort into getting a group, and MAYBE requres you to do mechanics. People that don't put in the effort shouldn't get rewards. Yes i am aware there needs to be things for casuals to do. They should get rewarded for it. Raid mounts that you can get from Flex raiding or LFR means it is worth nothing which saddens me. Over all i am in favor of flex raiding, but with it they need to removed LFR.