Perhaps, this for consideration, would a solution be to elevate the links on the Calibre web site to buttons on the Help page itself rather than (or as well as) being from linked text within the online manual itself?
There may be something I have missed (that not at all unusual
) but at present, from what I can glean, to get the downloadable manual after entering the website one opens the Help page, which takes one to the online User Manual that one then has to start reading in order to find the textual link to actually download the manual.
While this is clear to me now, so only a bit of an inconvenience going through that route (and as I say I may be missing something easier on the site), it did take me a few mental gymnastics to find it when I was new to Calibre.
All in all though, not a big deal in the scheme of things and other development.