I just don't ever have that hot of an atty or carto this time of year. I spend a lot of my time outside. I was up at high altitude playing in 3 feet of snow in my 4X4 today. It was a sunshiny morning and not much wind to speak of, but the thermometer said 6 above. While I was out in the snow, I was vaping my 5.0 tripple-v with a triple coil carto. Those things get crazy hot when used indoors, but are cold to the touch shortly after just taking a big drag or two outside in 6 above. It does transfer just enough heat to the triple-v (plus the warmth of my hands) makes that big chunk of metal nice and warm after a while. It's a good pocket and hand warmer when you use it often and chainvape some.
I know what you're saying about some attys getting really hot indoors, though. I mitigate that by being surrounded by PVs with different set ups (different attys cartos, and juices - many devices even at different voltages) so I can vape quite a lot and often whatever PV I picked up first and had in my hand for a while will get set down and might not get picked up again for an hour or more so they have plenty of time to cool.
And, also, most of my mods are aluminum. Aluminum is a great heatsink material. Nothing runs as hot on chunk of aluminum as it does on a plastic box or other good insulator. Insulators like wood and plastic make matters worse for an atty to cool. The aluminum, though the mods do get warm and probably transfer a lot of that heat to the battery compartment, removes a lot of heat from the atty connector and therefore the atty too because the atty sheds heat to the connector.
If I ever find myself vaping indoors more, or definitely when it's hot out next summer, I'm going to follow your advice. The less heat that makes it back through the connector in to one of my mods the better off my batteries will be in the long run.