3 per chair isn't really ridiculous when you eq up the bottom end to counter the sub 40 hz roll off. I had 4 on a couch frame in push pull, bolted onto opposing sides of a 1 1/2" laminated birch panel, and with eq on the bottom end, it was just enough at moderate levels. The levels need to be carefully set so that they aren't distracting, when balanced they add a greater sense of envelopment.
"What the heck was that crashing noise?" Me: "oh, just tossed the shampoo bottles off the shelf on the opposite side of the house. "