After giving to Google the necessary authorization for Flickr, my contacts were sent over, after which Flickr was able to match against existing Flickr users. I was able to individually control which of those users I wanted to add as a Flickr 'friend'.
the process was smooth and painless. Eve showed up as a friend afterwards.
The sequence was definitely not slowed down by any mechanism by whicn Eve might have been able to express her willingness to be added to my Flickr friends list. I guess by her sending me that mail last year she granted implicit consent to such operations.