My personal observation with my son is that when ever he tries to adjust his swing speed to make contact, it just ends up being a dribbler. I would rather he maintain the same swing speed, even if he misses. Yes there are situational times to do this, but in most cases a weak dribbler doesn’t do any good. Maybe should not be 110% swing but as hard as he can consistently swing and maintain control/ mechanics. Then you just have to focus on when to start your swing???