Interesting question! I understood, from my brief intersection with TGM, that lining up the right forearm with the shaft was the way to support the club through impact, to create the heavy hit, and/or to sustain the line of compression. If there is, as MJ in the release thread argues, at least in the best swings, no force against the shaft at impact, and thus no heavy hit or sustained line of compression, how would it make a difference to have the forearm lined up, above or below, the shaft at impact?