I don't know that I ever heard the cheer, but I don't know that I didn't either. I know that in one Air Force unit I was in in Texas, there was a traditional cry of "reality check" to be answered by all within hearing, "Him, him, fuck him!" It never made any sense to me, but if it came from the chant you posted, it's easy to see how the "Dear Mom" part would have been changed to "reality check."

(If I ever did hear this, it was someplace that had both alcohol and off-duty pilots. I might have had some of the alcohol.)