OK, I checked some access logs at random looking for the ++++++ type strings. I was wrong in one regard.
When these pseudo-referrers appear, its only in the FIRST page downloaded from my site.
The same person could view many pages, only the first record has the +++++ junk.
From what I see now, browsing patterns look like ordinary people looking around normally.
What they have done is to mask off the user agent which sent them, be it an incoming link, a search engine,
or a manually typed / bookmarked URL.
I don't see much use for it, I can't tell who's visiting whether they use this gimmick or not.
In any case, this looks very innocent. A dedicated bad-guy would want something much less obvious. -Larry