An odd realization on the way to defining "real D&D."

So I'm thinking again, as I sometimes do, about how I define "classic D&D" or, to put it less diplomatically, "real D&D." That is, editions of the game that I consider worthy of the Name and playable without reservation.

It seems that there are three very specific rules that appear both in every single "real D&D" iteration and in none of their lesser aspirants:

a) Alignment language

b) Encumbrance measured in coin (cn) units

and

c) The designation of one player as the party caller

These three traditions all dropped off the map completely in the post-Gygaxian era and haven't been seen since.

I can't think of any other long-standing rules that vanished so cleanly from the published game at exactly that junction. How about you?