Originally posted by Horowitzian: No, but I will. Thanks for the suggestion!
I still would like some confirmation from someone knowledgeable on those Tausig fingerings before I drill any of them into my head...
I asked more or less the same question here some time ago (and for more or less the same reason) and and got no response. Anyway, I have been using those fingerings for some months now and they seem okay. I got them from somewhere other than Tausig; I think they are pretty standard.
But if you want to get REALLY serious about thirds and other double-notes, take a look at Moszkowski's "School of Double Notes", op. 64.
I'm not serious enough to tackle that, but I have been supplementing scales with various etudes in thirds, too, to help keep from getting too fixated on just the scales and those particular fingerings.