I wore a satin dress at National Collegiate Dancesport Challenge last year and Mid-Atlantic Championships last February in bronze and no one gave me any trouble about it. I did however bring a spare shirt/skirt combo just in case someone decided to. I'd say plan on the satin being ok, but bring a backup. I always bring a backup in case something happens anyway. Better to be safe than sorry.
Thanks everyone! Joe...let us know what you find out...and thanks so much for contacting them. I was curious because I had this wonderful plan for a syllabus legal dress I was going to sew, but then I was reading the rules again and realized that perhaps satin was a no go...and this dress really has to be satin.
Basically, shiny satin in a 'no go'; however, if the satin is matte then it will probably be OK but as Mindputtee said, I'd bring a back up just in case. If you'd like to PM me a picture of the fabric - high resolution picture - I'll let you know if it will work.
As far as I am concerned, satin should be fine, even shiny satin (what's the point of satin if it's not shiny?). The rules call out "light effects" as rhinestones, sequins, beads, pearls, etc.
Ray Kaufman says this:
Satin is in general OK. This has always been an issue, especially with the PreTeens. However, unless it is really very very shinny it is OK. I know that this is a judgement call. I always give the benefit of the doubt to the competitor.