Actually, all this is should be pretty easy to prove if one has access to
virtual wind tunnels. All one has to do to prove an aircraft can not excede
mach 1 is to do tests on the suspected limiting factor. In the case of the
Me262 a 2 dimensional flow model of the wing or engine inlet should suffice.
Once you have determined a limiting factor it makes no difference if the rest
of the aircraft could have done it.

While such tests are not the same as real tests does anyone have an Me262 they
care to sacrifice?

Dan, U. S. Air Force, retired