WotC D&D editioning does makes sense if you base the numbers on game lines rather than revisions.
1 - OD&D, B/X, BECMI, etc. The original non-advanced D&D.
2 - AD&D. A new game line concurrent with "basic" D&D.
3, 4, 5 - the WotC editions, as numbered. Each is basically a new game, non-compatible with prior editions. 3.5 and 4E Essentials don't count as new editions because they're both revisions/refinements of their contemporary game line; and in the case of Essentials, still fully compatible.