Very fair points John, I have to admit.
The rumor for Team Sky is that they've used motors 'at strategic points in specific races'.
Fwiw, I think the following riders are using and/or have (at various points in their carreers) used:
Lance,
Cance,
Evans,
Contador,
Froome,
Sagan,
Hesjedal,
Hayman,
Van Aert,
Van Marcke,
Roglic,
And of course Femke, may God have mercy on that girl.
That's only the riders i've seen some form of evidence for (evidence here being any kind of issue that is consistent with and/or most easily explained by assuming a motor).
In addition I've heard rumors about BC track, Team Sky, Movistar and Cervelo and (though no rumors) I have reason to think Cannondale/Liquigas and Orica and some other teams (e.g. Lotto) are on to motors too.
That's what I would call "widespread, especially at the top end".
To conclude, there is also the Stade 2/Corriere della Sera investigation.
Over two races they caught a total of seven or eight (not sure) riders with suspicious heat signatures.
So fair enough, I should probably not use the word "widespread".
But I do think a fair share of the world's very best proriders (in various disciplines) are using or have used.