interestingly that feature was there April 2015. I was able to make a pdf of the sections I wanted. For example the complete list of (java agent) metrics (65 pages). Something to throw at my users when they ask what metrics does Wily show (yes still called wily in some circles.
The first reason I liked pdf (or ePub) was that I could read them off-line on my pad. The second reason was that the web site was failing for me. The navigation on left was erratic and would only show the current sections (and very slow refresh). The right side had no button next to go the next topic and since the left side was broken <pain>. There was a third reason: in some cases the user does not have a working login (and does not care to get one) and I want the user to read before calling support.
I am pleased to report that as of late, much of the navigation hassle I experienced last year appears to be gone (Chrome and IE11) and content becomes better every month.
The only linkage I found that is not yet working without proper support login are the "compatibility guides". That said I still miss the 'next' (or flip page) to navigate to the next page/topic.
Another thing that appears to work better is the search. I like searches to get straight to the section I want, example (v10.1): "Java agent properties" but "Java agent metrics" does find that section I liked in v9.7.
One note, as the older versions will go out of support I would suggest you to archive these, but leave them on the web for the administrator who has agents way beyond the support date.
I do like comment pages to report problems missing information or whish for more right then and now, but once that is done I hate to see pages of old comments or seeing them clearly ignored (or the thanks, hello, stuff that does not add value to the doc).
I really like, kudo, to the team, that when we open a support case and it is found that the doc is not clear or incorrect that the page is fixed within days.... tell your management to keep you guys funded.