Japans as far I know they didnt have impact grenades but a grenade modded for be a trap,soviets not sure at all
They are gonna nerf it like the WP, and it’s going to have less radius than the Explosives. Mark my words.
To be honest, I am against directly weakening impact grenades.
I think the biggest problem is that players carry too many projectiles rather than too powerful impact grenades.
Too many is the main problem, with a squad of riflemen capable of throwing up to 27 impact grenades.
My personal opinion is to weaken the large grenade pack. Without the large grenade backpack, players can only carry 9 impact grenades at most.
Besides the fact that some army’s don’t have them, is most concerning, for all, or none.
Maybe back packs could be BR tied 2-3-4-sort of thing,
you can only carry one type of each gren for large?
just silly idea 
curious