1. We have a different view of static typing than Racket.

2. We have a different view of the type language than Racket.

3. Long term, we are working on smoothly integrating testing, types, and specification [as a spectrum -- perhaps even as a cycle -- rather than as three different things]. Refinements are an instance of this. Another is our plan for how to do type inference.

4. I am also convinced that parenthetical syntax has real problems that I can't completely ignore. Of course, it doesn't hurt if it can get people to stop complaining. (It's not only students: the bigger opposition often comes from teachers. Unfortunately the teachers control the path to the students, so their views _really_ matter!)