You may be interested in my latest crotch strap experience.

I'm still analyzing my June 2003 accident and the cause. More later on this.
The role of the crotch strap is significant and worthy of mention.

Dr. Byars, thank you for this interesting and important feedback based on real
world experience.

The standard line from the German manufactures is that a crotch strap is not
needed because the submarining hazard has been taken care of through use of the
"H point" when locating the anchoring point of the lap belts. This system
locates the lap belt a bit further forward than in older designs with the aim
being to get the lap belt lower on your hips. This is supposed to prevent it
from being pulled out of place when tightening the shoulder harness. It does,
but I believe the lap belt has to be tightened to an un-necessary degree to get
anywhere near the effect the "H point" is credited with bringing about.

My experience is that the "H point" is not adequate to keep the lap belt from
being pulled up when tightening the shoulder straps. This is especially true
when flying out west in strong lift at high speed. A crotch strap helps keep
you from bouncing around thus providing more comfort and better control. The
difference is security in the cockpit is dramatic. I normally retro fit a
crotch strap to my gliders and feel a lot safer and more comfortable with its
use. This holds true even with my Genesis which used the "H point" system to
locate the lap belt anchor points.

Robert Mudd