Pace appears to be obsessed with the idea that a collision between a locost 737 flying out of a regional airport and a glider who in his opinion should not be there is likely.
My understanding is that the holiday bound (or returning) 737s spend as little time as possible at low level (i.e. below say 12,000ft) for good economic reasons. The flight paths into and out of these airports are well known and sensibly avoided, even if it would be legal to fly IMC in a glider there. Unless planning wave flying, gliders do not normally carry supplemental oxygen, and therefore do not climb above around 12,000ft.
The higher risk, I suggest, is to smaller business jets positioning to smaller airfields which are capable of handling them. A poster whose contributions indicate they fly such operations has said they often do so at relatively low level in the open FIR, rather than airways, for convenience and economic reasons (even when that option is available).
I hope they avoid flying just below cloudbase on days where the cloud is mainly cumulus; that is where a higher density of gliders is to be expected. The lack of collisions so far, and of airprox reports indicates that this is the case, and 'big sky' is working.
If positioning bizjets would like further reassurance that clouds ahead are glider free, then listening on 130.400 will give further confidence.
I have only one COM set. My most likely risk is another glider on the days when cloud climbs are desirable. My responsibility to the most likely conflict dictates my mode of operation.
I fit FLARM as the only current option available to me to further reduce the risk.
I agree that a fully interoperable system would further reduce the already small risk, and believe the obsession within the CAA that Mode S is a good answer, and the only answer (neither of which are backed up by the data available, or technical considerations) is unhelpful.
Meanwhile, I hope not to meet some of you gentlemen (meant in the nicest possible way).