I'm left handed.
My left thumb is a little off kilter from a ski mountaineering accident.
When I use the 1911, I:
-Disengage the safety as soon as the gun is level out of the holster.
-My left thumb goes UNDER the safety. If I ride the safety I lose a piece of meat out of my thumb. Thumb over thumb grip.
-Whatever happens while the gun is out the safety stays OFF. Finger off trigger as appropriate.
-When I head back to the holster safety is engaged, thumb is placed on hammer until gun is holstered.
I can shoot a 1911 riding the safety with my thumb over right handed no problem.
I practice one handed shooting, either hand, from the draw, from the hip and from retention. Safety comes off, stays off, as soon as the gun is level.
As far as the issue of remembering to engage the safety before holstering as a reason to engage the safety as you draw the gun back:
-I carry a USP C .45. DA/SA. When I'm done with a string of fire, I HAVE to remember to decock before I holster. I have never seen this as a problem. I NEVER decock it between strings of fire if the gun stays at the ready. In the single action mode this gun is no different than the 1911, except for a longer take up on the SA trigger.