Moon,

I meet many people involved in the dreaded "MX flex."  It did go through some extensive "envelope" changes, many of which I was not privy to in that they were before my time.  I was heavily involved in the final end product and can unequivocally state it is a sound robust design that is indeed "failsafe."  I have worked a great many Defense applications and I say to this day I have never worked with a more professional group or have more certainty of performance than the MX; PeaceKeeper.

BB