It seems that Flarm will give you the "ability to see climb rates of
gliders out in front" either through
* PDA software processing
* seeing a large gaggle which is a good indicator
* seeing relative height change between you and others while circling

I think this will increase gaggling since it will be even more
important to start last. Result - everyone starts late.

So, I think, Stealth mode will be a requirement in comps. If a pilot
switches to Open mode then there should be some kind of penalty.
Switching back and forth between Stealth (when things are peachy) and
Open (when low) should not be allowed.

Peter