411A , I am betting you never shadow the controls as you have enough skills and experience to know how far to let an FO go and when the line is crossed just take full control.
You would win that bet, I never interfere, unless a dire situation is developing.
If when acting as a TRE you observed a Captain "help" an FO with unannounced control inputs, what would you do ?
Suggest that he find somewhere else to work.