I haven't flown proper IFR in the UK, but having an instrument rating allows you into airways. The way I understand it is to get into the airways you need to be cleared in by a radar facility, and once in the airway is its own piece of airspace, so effectively you're cleared en-route. I'd like to see a similar thing for IMC holders, maybe the lower half of airways or something, without the need for all this FM immune nonsense.....oh and bring IFR approved GPS in while we're at it
Cheers
EA