This is an instance of a classic untestable hypothesis, and...

This is an instance of a classic untestable hypothesis, and hence utterly unscientific. Once upon a time when I was doing research I experienced similar situations several times. Just absurd, specious, always deriving from a quarter that felt threatened, usurped, envious, etc etc. This 'engineer' has imbibed too much of the entrenched Mcdonald Douglass culture and is likely smugly enjoying his moment in the sun having lacked the ability or imagination to make his mark otherwise. Amazing that internally no one has countered his mischief making, guess that's an indication of how far Boeing has fallen. Once upon a time he would have been looked upon with incredulity. Little wonder Boeing is one shipwreck after another if this is typical of quality of their engineering