The new way to do this is
JJJ Enter NNN JJJ...
It took me a few weeks to get that they changed the behavior.
You may also use '+' to plus a post and hit '?' to get a help screen.
So, the functionality to use G+ without the mouse is mostly in place.
Not to say that this works flawlessly. There are real annoyances like
- for articles with an image the first comment is usually not visible (despite 15" screen real estate).
- actually pressing Enter does not scroll to the first comment
- Nor does pressing N for the first time after Enter
- Enter is overloaded (depends on the currently active item (e.g. the '+' bullet or a comment))
- 'N' often and seemingly at random times does not move down but up instead so that it often needs three or more 'N' in sequence to get to the next article
- sometimes actions like following an article's link fail and the page jumps to the beginning instead
- The help screen says '/' is for search, but this has no effect at all
- there are no advanced search facilities for searching specific scopes like specific circles or communities, articles for which I gave plus one or I commented on.