"Brent" wrote: (clip) When you remove the tailstock (for finishing off
bowls, for example), the headstock moves back into proper position, and now
the wood will be 'off center',(clip)
^^^^^^^^^^^^^^^
I don't think this is correct. If the tailstock pushes the headstock upward
and off center, the work will still be revolving around the spindle
centerline. Removing the tailstock pressure would allow the headstock to
settle back to its "relaxed" position, but the work would still be revolving
around the spindle axis.

I suspect that what is actually happening is that there is some deflection
of the wood within the chuck jaws (or wrt whatever you are using.) This
would make the wood revolve around a "false axis."

To follow my reasoning, imagine that you turned a piece with the chuck
revolved horizontally to an off-axis position. Can you see that you would
be able to return it to the on-axis setting without introducing any wobble?