I don't consider that an erosion.
I mean, you can decide what it is for yourself, but the fact that they are providing less to no fluff on it at all in the very recent books (for PA, back to back) as they go along sure looks like a previous fluff removal to me.
...would have gotten the ''Combat Doctines'' system ... would also possess a ''Combat Doctrines'' system.
Well according to the Designer's Commentary, the Combat Doctrine system was always meant to be rigid. That was a very recent publication. The Combat Doctrines are intended to come across as a rigid system of tactical precepts. I don't know about you, but that doesn't seem appropriate for the Space Wolves lore now does it?
Not necessarily - I think we can all agree that the way Grey Knights fight is so far removed from any other Marines that their manner of warfare wouldn’t logically make any sense to use weapons they don’t have at all to do something they can’t do. There are no “Devastator equivalent” Grey Knights, while there are “Devastator equivalent” Space Wolves and the general manner of use is to provide long range fire-support.
Chaos Marines are similarly not currently trained in the same ways of war as modern Astartes - if these “ways of war” are old enough to date back the Horus Heresy, then at the least, not all of the Chaos Marines are going to have the same training.
I don’t agree with you about the doctrine concept suiting the other non-Codex compliant Chapters, but we’re just going to have to disagree on that, because it is probably going to come down to interpretation and mental picture of those other Chapters.
I’m not part of the development of these things, so I’m just going by what they wrote in the book fluff - I’m not going to deal with outside sources as “Word of God” on what the doctrines were meant to be (such as the Designer’s Commentary) or what Warhammer Community says they are - if the details were important enough to be included, then they should include them in the actual books. “Word of God” is easily changeable, reinterpreted, or given from a single perspective when an entire team may disagree and determine to re-write in later material.
If this was a retcon, it seems to me like a lazy retcon to justify giving the Space Wolves Combat Doctrines, instead of giving them a similar treatment to the Grey Knights. GW didn't even bother to rename the ''Devastator, Tactical, Assault'' naming system into something more appropriate for the Space Wolves.
It’s totally lazy - I’ve been very clear on that - I don’t like the way they did it or their justification at all. I will accept it, since fluff-wise they seemed to shy away from the actual fluff of it being a Codex thing, given the progressively less fluff included about them, but I don’t like it - hence my ranting about GW
spending just a little bit of
time in trying to make things fit the more unique situations (and that goes for other non-Codex compliant or “forcibly” (as in GW
seems to have changed their nature some to ignore their non-compliant methods) compliant Chapters as well.