Contrary to popular belief, the sight-reading section of UIL is a public performance, and anyone may attend as long as they don't interfere with things, or record it.

If you're going to insist that no directors sit in on the SR section of evaluation, then you are also going to have a tougher time finding judges to judge SR for the early dates as a very large number of them are still active directors in their own right.

Besides, the "prior knowledge" caveat doesn't apply to the director, only the student performers.