IMO, they just reprinted the C5 manuals for the most part.
Again, IMO, this all stems from the original early C5 bikes which had flawed handling due to poor geometry in frame/suspension. The bikes were very twitchy at speed, speed wobbles, etc. Well documented. The "fix" was to use a low pressure in the front to slow down the response of the front end by a underinflated front tire. Later models has changes to fork and front wheel to correct the matter, but the manual was never corrected. They never admitted that there was any "design error" probably to avoid the cost of a recall.
So, to this day, you see the low pressure spec in the manual.
Sad.
I have been recommending 28/32 for years, and still stand by it.