In article ,
Paul Kierstead wrote:

In (1), why doesn't he roughly make it round?

No reason you couldn't, if you liked. One possible advantage of just
turning the faces flat is that you could then move the center at the
next stage (it's oten difficult to tell where the best appximation to
center is on a fully rough hunk of wood). Of course, you could also just
move the centers at that point and turn it round between centers. Some
folks simply prefer working with centers, and others prefer not working
with centers. If you happen to have a lathe with a bad tailstock (one of
mine is), the latter position is wise.

In (2), why a glue block instead of a chuck? Strength issues, or perhaps
the because the tenon wastes a little more wood? Or just in case you
don't have a chuck (he seems economically minded); he does point out you
could use a jam chuck for (3)

Faster (hot glue) and less fuss for a lot of things, as well as a nice
tendency of Darrel not to act as a salesman for many tools you don't
actually need (as with many folks that have been at this a while, I own
a chuck, but I got by without one for many years, too). You could also
hold the things (in the hole, to do the bottom) with a pin chuck if you
were making a lot of them and kept the hole the same size.

I am just trying to understand the principles and concepts of turning
rather then follow a formula....

Primary principle - whatever works for you, works.

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