I never retrofitted to the comptip mast and I wonder if the extra weight is what causes that slow turtle on your 16. Do you have a comptip mast? Did the 14s get changed to comptip? The reason I turtled that I remember was a 25 to 35 mph wind blowing on the tramp with the mast still downwind.
Not sure if the 14s ever went comptip, the '75 we have is all aluminum again. Your H16 turtle experience you describe is the same scenario as happened to me.
This past Saturday I ran two empty gallon jugs up the H14 mast with the sail (tied to the halyard shackle) and when we capsized the mast stayed right at the surface. Also, the new righting system I installed made getting the boat back up much easier.

Thanks for your input!