USAF has been battling this for nigh on 20 years now. In the mid '90s, there was a push away from AF Regulations to something called AF Instructions (complete with a little phrase on the front that 'compliance with these instructions is mandatory' - as if to remind you).
At first, it sounded like a good idea. On Hercules, as other types, we had our 55-series regulation. AFR 55-130 (the last three digits were typically your airframe) and it was all in one place - everything from basic flying rules to how to employ the aircraft in various tactical operations. It was a hefty volume, but the information was organised well and each chapter specialised in a specific area.
We moved to AFI 11-2C-130 Vol 1, Vol 2, & Vol 3. Additionally, our basic flying regulation (like JSP 318) was divided/combined and added to going from AFR 60-16 to AFI 11-202 Vol1, Vol 2, & Vol 3. We then subdivided our tactics manuals and took out the Hercules specific chapter from 55-130 (that lived in the safe) and made two ginormous volumes called AFTTP 3-3 (unclassified) and 3-1 (classified).
On the surface, this seemed a good idea. Tailored information specific to the operation at hand. In practise, it's a dismal failure. Each publication points to the other one, they are owned by different offices and updated on different cycles. Additionally, they commands no longer "own" them and they must go all the way to HQ AF for approval - a process that takes about 2 years. It's horrible.
General knowledge at the crew level has suffered immensely. It is difficult to study anything without breaking out three books, at minimum. And the content changes at the whim of the latest staff officer. We've had a lot of stuff just fall out because one pub thought it should be in the other pub and the other pub thought it should be in the first pub. Sad, really.
We've corrected some of the deficiencies by writing local SOP guidance, but now we're adding yet another book to an already four foot high stack of books for our crews to be knowledgeable on.
Our books are so poor, they were cited as a CAUSAL factor in a mishap just a few years ago.
It really is a sad state of affairs. Sorry to see the RAF going down this same road...