[Switzerland] it is/was the only country to grant the UK IMC privileges in their airspace
Do you have a reference for this?
It's pretty amazing.
Not worth anything now though because the present-day ANO restricts IFR privileges of the IMCR to UK only. This change of wording was put in within the last few years.
Switzerland is the only place in Europe (that I know of) which permits a BRNAV GPS to substitute for an ADF, for en route IFR in CAS. That is pretty amazing in itself, by European standards.