OK; that does narrow it down – many thanks.
What this means, and I am carefully avoiding the much more obvious stereotypical example here 
is that if e.g.
then somebody on Gmail is likely to discover your real name by typing in [email protected]
Well, we all know Google owns the world, but this is IMHO going too far.
There is probably a vital step missing (because some Gmail users are unable to replicate this) but clearly it is a fairly easy step to make, whatever it is.
More tests…
Two more people have now reproduced this, using clean computers and clean gmail accounts.
If you start up your gmail account and send an email to my email address peter@ (you know what) .co.uk then log out of google, then wait say 10 mins, then log in, and start typing “peter”, Google offers the “joe Bloggs” name.
It was definitely due to Google associating an android app shop username with the email address used in a Gmail context. And it happens at the Gmail server.
As I said, for some people, a potentially nasty breach of privacy.
There is no obvious way to avoid it apart from totally avoiding using Google for email.
I’ve done a few changes and the “joe Bloggs” association with “peter” may now go away…
Frankly, ‘Google’ and ‘privacy’ in the same sentence is an oxymoron, methinks. Call me paranoid, but I avoid using Google for browsing (i.e. Chrome) and emailing. You really don’t need them for these tasks.
I agree re the privacy, but it is just so addictively seamless across PC, tablet and phone.
One more data point though, I just realised that not all my contacts had the blue head and shoulders icon.
It seems to mean that there is a “Google+” contact association.
(Some Google+ contacts have a photo instead of the default icon).
If I start an edit on such a contact, I see something like this:
Google+ profile:
connected via: peter@xxx co uk
joe Bloggs
Yes I think so.
To try to remove the association, I did a few things, one of which was an attempt (not sure if successful) to kill my entire Google+ existence. I am not sure what this actually is but it appeared to include my old Youtube account, which I could not login into after the Google takeover of Youtube, some time ago. Google+ was associated not with my peter2k email address but with my business address!
Stupidly, Google replaced the Youtube login with a Google one, which happened to be the one in use for Google Analytics for my business website! So my Youtube videos instantly became associated with the name of my business. No harm done but I don’t want my customers to see my hobby!
Nowadays I use Vimeo which is much better than Youtube (except they are more pro-active than Youtube in this area) but I also give them $50/year to keep adverts off. Consequently I am going towards self-hosting for videos, since I pay $20/month for hosting peter2000.co.uk on a nice fast server… and the great Handbrake tool enables the generation of .mp4 files which start playing right away.
It would be interesting to see if the “joe Bloggs” automatic name fill disappears now.
A further report… it still happens.
It turned out that I did have my normal email address as a “backup address” in the google app shop. Yesterday I removed that backup address, but it has not made any difference. So either Google retains associations “for ever”, or it simply does what I said above i.e. connects up various bits of data available to it.
Well, we know it connects up data (their Ts & Cs allow them to do that) but the dodgy bit is that they pick up a name used in the android appstore and present it to potentially any Gmail user who references that email address.
It’s only a matter of time before that causes a real problem for somebody, and then they are going to get sued.
