He was one of the most recorded percussionists during some years - he and Steve Gadd most of the time, e.g. on those CTI albums; or he and Harvey Mason, e.g. on George Benson's Weekend in L.A. - that's a good example of what he could do.
He invented a lot of ideas and licks that just about everybody copied, myself included. He was very influential and one who proved how adaptable percussion could be - later guys like Bashiri Johnson are unthinkable without Ralph MacDonald. I caught him live with Steve Gadd on the Frankfurt Music Fair - very unpretentious guy. He was honoured last year on some convention, already confined to a wheelchair ...
R.I.P., and thanks for everything.