The truth is that no move is 100% effective. There's always a countermove for everything. And if you cannot find a countermove then always improvise. Bruce Lee is the best example of this ideal. He always taught to his students that when being choked and you are in a position where there's no where to go because you end up hurting yourself, what you have left is to bite, since is the natural instinct. If you are grabbed there's always a way to get free from it. Do not tell me that a grappler have a higher chance of winning than a striker because if a striker throws a punch to your throat or pokes your eyes or grab your private parts and squeeze on them, tell me how effective a grab or take down would be? Also if you have a perfect standing position, no matter how great a grappler your opponent is he should have a hard time trying to take you down, meaning that the guy with the black belt that got beaten by the white belt grappler doesn't have great legs, learned a defense class that only trains for tournament purposes and is not a real martial art or they gave him the black belt and doesn;t train much.