Hi Jeff
I remember seeing Capt Sensible singing Happy Talk on Top of the Pops as a kid, don't think it was used in a tv show or advertising, though somebody will probably correct me(!), I think it was simply a cover version.
Just going back to the footage I saw of Carreras singin Maria, I'm not sure I agree with your comments Jon.

sorry!
To say only Americans (or those with American accents) should sing Maria is preventing many other wonderful singers from tackling the song.
I didn't see the original broadcast of the show, but it appeared to me to be a special project, so let's not forget that.
I must say that I know very little about opera and in particular singers from the genre, but I do know that Carreras as a singer does not appeal to me, he is a bit 'rough', or he can tend to shout. However, that being said I did think he sang Maria with so much passion and feeling, that his accent and other traits didn't seem to matter as much to me.
Just my thoughts, and I know very little about music and so I would always bow to others better knowledge
Must dash, work's calling!
Gray