"This is a major restoration of a landmark television comedy series that deserves to be reappraised and seen by more than just Abbott & Costello fans. Yet another major save from the 3-D Film Archive."
https://www.dvdtalk.com/reviews/review/75130
To be honest, you're right. Most would have been content with using the fine grain audio. It would certainly have been easier - and much cheaper. Once we did a test and heard the difference, there was no holding back!
John, that issue is addressed in several commentary tracks, I believe ep 6 by Ray Faiola and ep 14 by Ron Palumbo.
The opening cue is “Abbott and Costello Main Title” by Raoul Kraushaar, published by Marlen Music.