Ray: The film soundtrack take of "Deep in My Heart, Dear" actually consists of several partial takes. In fact, the only
complete one-take version that I'm aware is the one featured on the Sepia CD
The Undiscovered Mario Lanza (also featured in a different reproduction on the Damon Lanza Productions private CD
If You Were Mine). The version featured on the Rhino CD
Mario Lanza at MGM uses the same intro by Mario as the Sepia version, but is a different take from Ann Blyth's entry onwards.
The film take is the smoothest version overall of the three, with the Sepia Undiscovered version a close second. What mars the latter is Ann Blyth's mis-pitching at the end, which seems to throw Mario "off course" as well. It's clear that she was having pitch problems that day, which is probably why there were seven takes (mostly partial) recorded, according to the MGM logs.
As for the differences between the three versions that we do have, apart from the different endings on all three, the phrasing by both Mario and Ann is quite different from their duet portion onwards. To demonstrate this, I'm attaching an MP3 of a brief part of the duet. The first take you'll hear is the Rhino version, followed by the Sepia Undiscovered version, and then finally the film soundtrack version, as featured on Sepia's new Student Prince disc. If you listen to the end of Mario's intro on the first two takes, you'll hear a slightly rough "forever" on the line "But I'll remember forever". (It's the same recording both times.) But on the film take, "forever" is smoothly delivered. There are then marked differences in the way Ann and Mario deliver their respective lines "I've waited a lifetime for someone to say..."/"And darling I mean every word that I say" in all three versions that we have.
Happy listening!
Derek