Have Rengar's passive brush leap not proc if he is in certain vision

Vision being direct champion vision (they are sharing the brush) and control wards (because they are special and have the word "control" in the name).

I feel that having the ability to just spam his leap even in full view of champions is a bit odd. As a predator, the element of surprise is one of his major tools of combat. Suddenly jumping out of a bush he was hiding in onto a passing squishy is what he is meant to do. But if he is not hiding in it, then he is not really using the element of surprise. SO it would make sense that being in vision would stop his surprise jump attack.

However, I feel that trinket wards and SS being able to negate his leap in fights is a bit too harsh of a nerf for him since they tend to be readily available and do not need to be purchased over and over again. They either just come off of CD or get refilled every back.

So because you would be spending the 75 gold and sacrificing the item slot, it would justify having control wards disable his leap. And if a champion is right next to him in the bush, then again, there is none of that "surprise".