Fascinating discussion. Permit this old boy - who first went solo in a glider in the early/mid sixties and got his gold height in Cb – a few words. Unfortunately, finances now limit me to a month or so a year gliding in Australia each year. No cloud flying in gliders there.
I read this subject as much about VFR as about cloud flying and an attempt by the ATC fraternity to control all airspace. Transponders on everything? Perish the day!
The airspace rules have been changing and evolving over the years. My guess is that few have kept up with the all the changes and, if asked, would struggle to give a clear concise explanation of classes of airspace and the VFR/SVFR/IFR stuff. The attempts at some new simplified Euro 3 classes of airspace may simplify matters but this old carbon based brain struggles to keep up with the requirements in different countries.
I rather suspect the ‘let out clause’ allowing gliders to enter cloud is as much to avoid the issues of cloud separation. When wave flying you will invariably be closer than published minima for vertical and horizontal cloud separation.
Cloudbase 3000ft does sometimes happen in UK. Soaring pilots will regularly climb to cloudbase. How can they maintain VMC minima?
At the risk of being found guilty of topic creep, are B21 and B226 still open to gliders crossing with ATC clearance.
Rgds
lars