Speed accuracy- how accurate is accurate?

@OP

zavato 

Certainly, running at 33.333333333333 . . . with a stylus in the groove is ideal

Not if the Music itself has been recorded a bit slow or fast

What IS important is to have easy control to make your platter faster or slower and ensure it stays there when set. imo.
 
Now if the turntable does not have this type of control, given a choice between running a little slow or fast - definitely faster is better.