The program meaning of designer fabric — meaning designer fabric

Does every designer fabric listing mean the same cloth?

No. Designer fabric is a retail phrase. On a mill page it should still resolve to fibre, construction, and mass. Ask whether designer means a named house, a print designer, or a price band. Those are different.

Can you skip sampling designer fabric?

Sample the named quality.

What should stay on the brief besides the keyword designer fabric?

Named cloth, spec, and tests. Assuming designer means better tests.