I know that. I actually was part of the discussion. Robbert was on a roll recently. I thought MAME would have (for lack of a better understanding)an interface with other pin sims of some sort long before it would do full fledged simulation of pinball. No other developers will do it better
With Couriersud chugging along with the discrete stuff, I thought MAME could eventually be the "go to" place to emulate pinball stuff for other sims.