Single post in Mega-Stones while scouring

I know no need to shout at me people have said this but i have betters reasons: 1:Pokemon can only find them in prefered areas 2:A smaller chance 3:Pokemon will find them only if you have at least 1 scour boost 4:The pokemons typing affects what stone they could get 5:The pokemon can only find one after exploring the area 10+ times so they can "get used" to the area I belive this is a good idea as it would make sense a pokemon COULD find one if lucky enough the bit where they must examine enough so they notice it wasnt there before and they chances are low. Disagree if you want i dont mind i just think it would be a realistic thing that could happen thanks for reading