You should only macro, as a DPS, Flaming arrow and the like to skip the targeting (unless you want to pre-cast, then do it manually).

The key difference you're not getting is "can" is VERY different from "should". You CAN macro a rotation, but SHOULDN'T. At 52 you should know sometimes fights throw a curve ball at you. Normally, this means maybe missing a GCD. If you use a macro though, you may end up missing many more and not know where you're at. Not to mention sometimes, you DON'T want to activate a buff. If you mistime it and the boss disappears, you're wasting the buff. You only get this fine control by doing things manually.

This is where practicing comes into play. Things become second nature. And think about it... if these worked so well, why don't we see them posted instead of rotations?