I think the good swing thought is: "Tumble tightly" ... because if you tumble loosely you will tend to get OtT.... and sloppy, excessively.
The scientific rationale for tumbling tightly is rooted in the force relationship of the hands and arms to the fast swinging club during final release.. when kinetic energy is surging down your arms and into the club.
Tight tumbling will not only ensure control of the clubhead path, it will also maximize energy transfer from the body to the arms and club.