I'd think I'd rather pay for Swiss insurance to make sure I have cover, rather than rely on uk.gov to pay for me in case I get trashed by a tram...

My *personal* opinion:
Isn't the EHIC card thingy is only valid for residents on holiday etc?
If you're not resident, say in UK, you're not paying UK taxes, so why would uk.gov pay for my treatment?
Otherwise, they could have a liability for all UK expats in the EU area.
I wouldn't like to find out I have no cover after the aforementioned tram has trashed me...