Michael,

Lets say the blades are flying off at 100,000 RPM
due to centrifugal load and 1700 to 1800 F exhaust
temperature.

The load on the blades is Mass x Velocity squared
divided by the radius of the CG of the blade.
The Radius is small.

If we limit the turbo RPM to 90,000 RPM
the load on the blade will be reduced 19%

10 x 10 = 100
9 x 9 = 81

If we limit the RPM to 80,000 the load
on the blade will be reduced to 100 - 64 or
36%.

8 x 8 = 64

There is not much we can do about the heat.

Paul Lamar