TV,
I can still see lots of holes in such a policy.
1) Let's say my routing was EDI-LHR-DEN and I had a puncture on the way to EDI. Well surely that it not an international departure point, as EDI-LHR is a domestic sector?
And just to be picky as my recent trip was similar - if I has BHX-CDG and then CDG-FDF (Martinique) as my routing, the second sector wouldn't be international either.
Or does it just mean any airport offering international flights?
2) There is no cover for the more likely scenario of dense traffic or road closure - so let's say you are setting out from St Andrews and the Forth Bridge is closed. No cover.
I would also expect a clause about allowing "reasonable time" to get to the airport in the first place. My general rule is check in / bag drop / gate (+security) closure + 1 hour.
Also, presumably no cover for passports / docs left behind at home or in the car, as happened to me for my departure from NEV. Fortunately, driver (dad) had only gone 5 minutes and he answered his phone (on second attempt) and promptly returned to airport.
As for b), I still see loopholes.
I would expect the insurer to claim (wrongly) that airlines do not provide public transport, as that term is generally used (wrongly) to refer to mass transport within cities.
Of course, you could point to dictionary or wiki-ref sources pointing out differently, but you still might have an uphill struggle.
Presumably, for the sake of this policy, a taxi counts as a car (taxis are certainly not public transport) - so again I'm not sure if the cover (against a taxi breakdown) is as relevant as a taxi simply failing to show up. This happened to me once, but luckily I had only ordered the taxi to take me to the bus to get to the airport. As the no-show of taxi meant I missed the bus, the taxi took me to the airport without fare - but I really wouldn't want to have been arguing that with the taxi co's lawyers!