Fair point. I know that Thom Mackris, who makes the Galibier tables, doesn't like the cantilevered armboard approach. He's said this to me over email, and I don't think he'd mind me sharing his stance. Anyway, I just thought I'd express that I've heard at least a couple different philosophies on how to best mount an arm. I'm no expert, certainly!
Likewise Harry Weisfield has stated several times that he doesn't like the idea of vacuum hold down, which is why VPI sells their periphery ring.
Graham Engineering and VPI differ on the best way to do a unipivot.
SME, Rega and Linn differ on how to mount an arm to an arm board.
Ayre believes in no negative feedback in their circuits, ever. Boulder and Pass use negative feedback as they feel fit.
…and so on.
Each company does their own thing and usually has a reason why other companies are doing it wrong.