Piedmont pilots will rationalize any deal they can get. Their MEC chair knows they are in line for jets and the senior cadre doesn't give a rats patoot about the rest of the industry. That is why he didn't sign that letter. His claims of it not "meaning anything" are just subterfuge to mask the real reason he didn't sign - SJS.
The simple fact is, they want those jets and will do what they have to, to get them.