It definitely screws with Combo's.... if you are synced down from a 40-50 monk, you probably have your bar set (if using a crossbar) with your flank combo and rear combo, and those abilities aren't all available in the sync down so the muscle memory of the abilities doesnt work.

I can see this being a fact primarily on Monk.... MAYBE on DRG too.... as a main Bard, not an issue.

I would assume BLM and WHM have this issue too, since there are alot of spells and the way you would group them on a crossbar may make it tricky..

For a tank... easy peezy... Your 3rd ability in combo shouldnt be active, so use the first two and spam overpower/flash.... thats how those dungeons were built.

System is fine the way it is... Not an issue, be more observant to the abilities you have.... unless you are just lazily leveling a class and spending no time trying to learn it.... in that case, you are just a weak grinding player