Bjarte Runderheim wrote:

I always start on the (normally) flat side that is going to be the
concave side of the bowl. I put the piece under the drillpress with a
2 1/8" Forstnerbit, and drill a hole near the max depth for my chuck.
I put the piece in the lathe, roughturn the bottom, and make the
recess for the convex side with a parting tool ( This tool makes a
clean, cylindrical hole).

OK up until this point except that I either use a woodworm screw in my
SuperNova chuck for smallish stuff, or a faceplate for the bigger
blanks. I have my doubts about the "cylindrical" nature of the recess
too, but that's been covered adequately in other posts ...

Then I true up the first hole with the parting tool to secure the
symmetry of the two holes. Then I finish the bottom, and I mean
"finish", as in sanding and oiling.

Now, this is the bit I don't understand. Are you saying that you reverse
the blank just to true up the first hole you made and then reverse it
again to finish turn the bottom? Why?

Then I "empty" the bowl and finish.

This is the routine I learnt from my local "guru", and it seems to me
to be very near a professional way of working.
--
Alun