Wed Mar 13 09:20:40 EDT 2013

Control rate

I see 2 ways:

- Stay in the same framework, and see it as an input (parameter) TX,
  where moving things outside the loop is treated as an optimization
  (meaning stays the same).

- Add an extra state processing step.

It's hard to look into the future for this.  Control rate ops are
going to be all over the place, so why not make them explicit?