I think is a good example for a different reason...
Firstly, there was a big time gap between the major releases of AD&D and D&D 3e (and honestly, a lot of people had abandoned AD&D for other games... a big push early in the D&D 3e was the attempt to win people back to the game... the d20 Wheel of Time and d20 Call of Cthulhu games were just such efforts).
The "big time gap" thing is deceptive, as TSR were pushing several different versions of what was mechanically the same game, and were pushing multiple campaign settings for the various versions of the system. I'd disagree with you, because they were in fact pushing lots of major releases.
Whether they lost a lot customers, I honestly don't know. I haven't seen the numbers, assuming numbers exist. That said, as a non-D&D player during that period my impression is that everyone who played RPGs played D&D and only a faction played anything else besides D&D.
D&D 3e was followed by the fairly rapid and minor revision between 3.0 and 3.5, different but not terribly so. D&D 4e seemed for come very hot on the heels of 3.5 and was a massive change in system to a game that still a fairly solid base audience. The fairly short perceived time between editions, combined with a fundamental change in direction and, seemingly, target audience, after a more incremental change, made the "edition shock" more extreme.
This is a very good analogy for the development of the 40K-RP line... each game within the 40K line can reasonable be seen as a different "edition" of the same rules set. We started with Dark Heresy and have seen minor, incremental changes every few years. That makes a massive change much harder for the established audience to accept.
3e came 9 years after the last major release of the system, and prior to it there had been only incremental changes to the more and less crunchy versions of the D&D system (AD&D and D&D). 3.5e followed another 3 years later, and again consisted of incremental changes only. 5 years later still - 8 years after the release of 3e - 4e was released. And like 3e, 4e was a major revision of the system.
What all this means, as an extension to your post, I guess would be that major revisions to products that are less than 9 years old cause system shock. And especially if we roll on the old AD&D tables, that makes it a very good thing FFG re-decided and are releasing nothing that haven't released before. Because system shock rolls in AD&D were pretty lethal, and dying from a revised RPG system would suck.
Tortured humour aside, I'd still rather have a single incrementally updated rulebook for all the lines than the current mess. And I still have more than enough issues with WFRP2.5e that I'd very much have liked to see the new edition of DH actually be a new edition - a major revision of the system, not just slight tweaks.
But I guess the playerbase has spoken... So I'll slink off back under the bed to resent you lot for it