We are required to include it as part of an outbrief by accessing the website - therefore not valid by the time you get airborne.
Well then, I agree - didn't realise that. That is simply daft. And apparently an example of "Something Must Be Done. That's Something; let's do that"
It might help gliders 'see' each other but it doesn't help a conventional TCAS equipped aircraft see the gliders.
No, but FLARM wasn't designed to do that. It was designed to stop gliders - deliberately flying close in thermals - from bumping into one another, as an affordable, technically achievable and proportionate solution to that particular hazard.
The technology must exist to have smaller and lighter transponders in light aircraft which would be compatible with TCAS users.
ADS-B OUT is probably that solution, but (civil) legislation in EASA land militates against it due to significant cost and hassle with limited direct benefit to those with a limited budget. It's different in US (as ever) due to the direct user benefits of ADS-B IN live in-flight weather/NOTAMs etc.
But we're getting away from H-C now. So responses to first para only probably relevant.