Thanks for posting. Firstly and most importantly, I hope you have fully recovered?

You make some interesting points about the lack of simplicity and the different policies when it comes to changing bookings due to sickness where you're flying with one carrier but where the ticket was issued by another airline. Based on your comments about insurance coverage for high-altitude activities I have just checked my policy (issued by Allianz, here in the USA) and it covers up to 15k feet. I think the highest I have been was to the Jungfraujoch in Switzerland and that's a little over 11300 feet above sea-level. I really did notice the effects of being at altitude, despite doing nothing more strenuous than walking around, having a hot chocolate and taking photos!

It's also only been the last two years that I have had personal travel insurance. I am covered for work trips via my employer and my health insurance covers me whether it's business or leisure travel but for anything else I chose to self-insure. I've never really had any issues or incidents where I would have needed it, but a couple of years ago I just felt it was better safe than sorry.