"Two of the tracks ("Your Daddy's Son" and "New Music") from the first CD were re-used on Rca's complete recording. Otherwise the 2nd album was newly recorded."
Actually, they were not re-used. If you notice in "New Music", the first verse is sung differently by the people singing it - Mother, Father, and Younger Brother, all sing at different times than they do on the full recording. (Besides the fact that the "ensemble" was a different cast than on the full recording - since those people are not credited on the complete recording, it is highly impossible that it was "re-used")
And there is a slight difference in the way "Your Daddy's Son" is sung...slight, but hardly noticable.
Let's not forget that there is a Symphonic Ragtime album - which means that technically, there are three recordings.
"Do you know what pledge time is, Andrew"? said the PBS Executive.
"Yes", Lloyd Webber replied. "My 50th birthday special must be one program that gets done a lot."
"No", mused the man from PBS heedlessy. "Not so much. Our Stephen Sondheim Carnegie Hall concert. That's a big one."
Spoons, forks and knives seemed suddenly to suspend their motion in horror, all around the table.