Is remastered mainly just less jitter?

also the 2002 or so re-masters of the Stones 1980s releases are supposed to be MUCH better

Most of the re-masters I’ve heard are just louder and more compressed.

Typical example was the Moody Blues On the Threshold of a Dream, the original Decca release is so much better than the MFSL re-master.
Sure the Decca was a "little" raw, but the MFSL re-master was blunted and fat, no excitement in comparison.

Cheers George

The Stones remasters in hybrid cb/sacd were excellent and much better than prior releases. Those remasters provided the greatest improvement over original redbook in the rock domain that I have ever heard. Remasters in general are a crapshoot.

I concur w/ The Rolling Stones on SACD (remastered), as well as, The Police on SACD, Van Halen (CD) and Rod Stweart (CD).  Otherwise, it is a crap-shoot.  Happy Listening!

The Small Faces Decca deluxe reissues have also been well remastered. I agree it is a crap shoot.