"Kevin Horton" wrote ...
The higher speed also gives more lift, and the lift to drag ratio (and
hence the glide ratio) remains the same. This assumes that both
conditions are at the same angle of attack, and the the changes in
Reynolds number and Mach number don't change the airfoils CL and/or CD.
This should not be a problem with typical light aircraft at their best
glide speeds at typical light aircraft altitudes.

You're ignoring aeroelastic effects. Some of the plastic airplanes can bend
quite a bit.

Rich