While the L/D max argument carries merit the problem is that one needs to have operational practices which fit into the real world. Slowing down to 220 (L/D max-ish in the plane I fly) while everyone else is going much faster isn't going to work. I think that, realistically, the best you could do is plan for a descent at idle with a .84/290/250 (or whichever figures work best) profile until the FAF as far as saving fuel and fitting into the big picture are concerned. Even then, this still isn't an option at many busy airports.