Don't forget that there's a very
large grey area between a 'comfortable maximum' (IEC 60320 rates that at a pin temperature of 70°C, except for the higher-temperature variants which may reach 120°C or 155°C when further heated by the appliance) and actual meltdown; I've previously run heaters (up to and including 2.4kW @ 240V) through (deliberately long and silly-looking) chains of IEC 60320 C13/C14 cords, to prove the point that it would still work (which it does)
They are mixed 0.75mm^2 and 1.0mm^2, and none of the flexes themselves get warmer than I'm comfortable with. So far, I've only had one pin actually melt the plastic (which I later diagnosed, by autopsy, as a really
bad crimp connection that didn't hold onto the wire at all!), but many
pins still get too hot to touch (these are mostly "modern" versions, usually from Chinese/Taiwanese manufacturers).
(But then, surely
a 10A-rated connector sustaining a heater drawing 10A is just the basic call of duty
I did have one other defective C13 socket, on a molded cordset made by CMA (back in the 1980s, at a guess). This, however, was a completely different fault: There was a bit of stray PVC in the active/line slot. This cordset ran cool while the connectors were properly seated, but the errant bit of PVC carbonized and created a nasty resistive path (releasing clouds of smoke) when I unseated the C13 end under load. And this one was a bit tragic, really, as the contacts themselves looked much
more robust than in newer versions.
(I salvaged it by cutting off the C13 end and converting it into a short extension cord.)
Apart from such occasional defects, though, the earlier molded cordsets were fantastic (if observed trends continue, they could well provide centuries
of reliable service)...
Between the "new" Chinese/Taiwanese versions and decent rewireable connectors, though, I think I'll stick with rewireable (for heavier loads, at least).