The East Sale military boys are pretty amenable. I have been in the area when they activated without prior warning. They followed a simple plan.
1. Made a general broadcast 10 minutes prior (i wasn't on ML cen due 1 com)
2. Made contact with all traffic seeking intentions.
3. Issued clearances according to peoples intentions.
4. did not divert any existing traffic to the VFR lanes.
5. Notified new traffic that the area was becoming active, and only diverted those to the VFR lanes where it represented minimal disruption.
It was busy on the radio, but the mil controllers were professional and accomodating. It was good to see as there was a fair bit of RAA traffic, and the controllers really helped those that needed a little guidance.
So yer, not something to be scared of.