If you are making a zirc bridge going over telescopes why do you feel you need a secondary to cement into the bridge. The bridge can be your secondary.
Obviously the span the amount of teles and the precision is MUCH more difficult but for a shorter span its easy. The fudge factor of the cement into the bridge solves some issues but we are almost always fighting for space.
CAD allows us to do some amazing things but sub 10micron fit for friction is better achieved with Galvano secondaries.