ATM Secondaries by Replication?

["Jim Miller" <jim@jtmiller.com>]

Have you seen any work done on creating a flat elliptical secondary out of
composite materials (carbon fiber/epoxy) through replication?

Separately, but related, I've seen some mention of the figure needed for
secondaries to be quite a bit less than that of the primary since the
secondary is so close to the focal plane that its aberations have less
"moment arm".  Do people needlessly over specify their secondaries for our
purposes?  You certainly don't want the secondary to limit the performance
of the scope when you've spent so much on the primary but...

...if secondaries don't need to be "perfect" to make the scope still
primary-limited and if replication of composites is economically feasible
for amateurs then all of the good things attributable to carbon fiber might
be at our doorstep (good conductivity, stiffness, light weight and low TCE)
especially given the small sizes we need for secondaries.

Thoughts?

tnx
jtm