Yes. The stuttering was on the web browser version.
I think if you keep the unintentional effect of the reflect barrier it should be moved to a different upgrade as I wouldn't expect that interaction (but I do think it could be fun as a different upgrade). Or, at the very least, it could be the second upgrade to the reflect barrier(?) It might also be fun to have your bullets reflect back at you? But then that would be pretty punishing for the grenade launcher...