The disc is somewhat irrelevant when the frame is wrong, mainly the heelcup nowadays. That is what's creating the <insert whatever> effect. The board and screws jump up and down and twist, while the heelcup stays put. Now you could say that a bigger disc makes a smaller lever, but there are solutions for that aswell, and big discs had the same issues on older bindings. That Union put foam in between the screws and inserts doesn't make it a whole lot better, on some bindings you gotta struggle to get the disc to touch the topsheet. A rigid binding can work just as well as a flexible bindings, but can't be made the same way. Deadspots are overrated, but fucking uneven density footbeds are painful.