Are my gunners retarded?

So, i have a problem with my tank gunners, my gunners are almost maxed on targeting and range finding, but for some reason whenever im moving (even if its just 1mph and a few inches forward) and i even slightly put on the breaks for one second and my gun swings around like i just fired a .50 while standing up, the thing is i expect that since my gunners are nearly maxed they should be able to figure out how to vertically move the gun while breaking but apparently not. idk how to fix this because it seems like no one else on the enemy team or my team have this issue and i regularly get one shotted while the enemy is breaking, so i would appreciate some help on how to fix this.