Feedback is totally unnecessary in scenario design. I postulate that it harms it.
Feedback is absolutely required in playtesting.
I realize that Scott is just trying to make an interesting thread, and provoke a discussion of what SSRs should be considered as acceptable. He doesn't really need our help to design his scenarios, so I'm teasing him a bit. What are you...his lawyer?
I don't know of a single good scenario designer who goes around asking for help with their SSRs...or anything else for that matter. Scenario designing is generally a solitary enterprise. I doubt many scenarios are "designed by committee", and if they are they probably suck.