Thanks to all for your thoughtful responses.

To summarize for green turning specifically
- sharp tools with proper presentation of the edge
leaves a smoother surface and therefore less
dings/tear out/shredded wood for bacteria, mold,
mildew etc. to begin living in
- turn wall thickness to two two three times the
final desired wall thickness
- "free water", as opposed to "bound water" can be
blown out of the wood with compressed air blown
from the inside to the outside (assuming the grain
isn't parallel to the axis between centers
- sun light and good air circulation discourages
dark mold and mildew growth - but you don't
want to have a hot sun, on a hot day, beating
on the wood as it may dry the exposed areas
faster than the unexposed area, leading to possible
cracks and splits.
- with open grained wood, sanding with oil will create
an oil/fine sawdust slurry which "can" fill the pores,
ultimately leading to a smoother final finish.
- rough shaped green pieces can be dried enough in
several days to a few month, depending on the thickness
of the piece, to be finished shaped and finished "dry"
- if you're going to rough turn green, have enough blanks
to work on while earlier green turnings dry

When turning green pieces with high contrasting heartwood
and sapwood (ie black walnut: heartwood almost black,
sapwood almost white)
- the dark colors will migrate into the lighter areas (steamed
walnut and cherry for example have less contrast between
heartwood and sapwood than kiln dried or air dried walnut
or cherry. the downside is that the colors won't be as
prominent - more towards blah brown than notable grain
patterns)
- it is preferable to turn the piece to its rough shape and
wait 'til it's dry to turn to final shape and finish
- if you're impatient and don't want to wait for the wood to
dry for final shaping and finishing
.. DO NOT SAND when still wet. You'll just drag and then
embed the dark sawdust into the whiter wood
.. if you just have to sand, shellac the green piece first,
let it dry, then sand - carefully so as not to sand
through all of the shellac and repeat the shellacing
between grits, waiting for it to dry before continuing

did I miss anything important?

charlie b