When you lock on to a target the shatter bomb when throw will move to where the target is moving at the time of when it was thrown so any target that is not moving in a strata line i.e. running to the left, then you throw the bomb, if they stop or change where there going the bomb with fly past them. So if you are a Gunner and you throw you bomb at a target that is moving down, but is close to the ground or your height then them the bomb will go down after then (where there would of been if the did not stop going that way, if not stoped by the ground/wall/roof) hitting the surface right next to you damaging you, why do you think most Gunner jump when in combat or at any time or run in crashes patens when on a chapter point, to move faster also to be harder to hit (sniped) and so any shatter bomb throw at them will ever miss or hit the ground near the throwers feet, don't throw the bomb in lest in the air if you wont to be sour not to hit yourself (if you land on the area where you throw you bomb at be for the bomb you can ges what happens.) In short its usher error for relying to much on the lock on.
There are people that have a resin for what that do and those who just copy what that see (because it works)
And sniping be the easy in till lag comes along (making the snipers shots shot of to the side of appoints apart where there not.)