Yes, we have had this argument before…and you are just as wrong now as you were then. Why would the wax be pulled into the pressure points? Outflow is easy to explain without having to go so far as to say that the wax melts even locally. What drives the inflow? If there were enough heat to cause the wax to melt even locally, the heat would build up and the chain would get hot with use. No chain I’ve ever touched during a ride is warmer than the outside air.

Looking only at the chainring (something similar would occur at the cassette), pressure on the pressure point would start to ramp up as the chain first starts to go around the curve of the ring. The pressure would quickly ramp up as the chain travels further around the ring but any possible melt shear would happen near the point where pressure first starts. If (and that’s a big “if”) the wax “slip melts”, it would occur at this point. If (and again a big “if”) the wax melts enough to become liquid, it would flow out of the pressure point. When the chain comes off the bottom of the chainring, the pressure quickly goes from on to fully off. Unless there is enough heat in the chain to remain liquid, there is nothing to make the wax flow back into the pressure point. The wax would solidify in place outside the pressure point.

Now consider if the wax is just plastic. Under the same scenario, excess wax is pushed out of the pressure point due to its plasticity. It still stays outside of the pressure point but the chain shows no heat. We are at the same place where the wax doesn’t flow.

Also consider the size of the gap between a chain plate and the pin. It is large enough for the two pieces of metal to move but it is a very small gap…on the order of micrometers (or hundreds of thousandths of an inch).The wax (or any lubricant) needed to fill that gap is likely to be on the order of micrograms. The roller is filled with wax (probably milligrams) and it should serve as a reservoir of wax. If wax melted like you feel it does, there should be enough wax in the roller for many thousands of rotations of each pressure point. The wax in the roller isn’t going to be squeezed out during the rotational process in any significant amount so the reservoir of wax should be practically endless. Oil will flow out of the closed system and needs to be refreshed. Again, wax doesn’t flow so it will stay in place until physically removed.

I will grant that some of the wax in the reservoir could flake off and be pulled into the gap through physical means…i.e. grinding…but there is no significant flow nor any liquid flow back into that gap. It’s not pumped into and out of the gap like oil is. That’s a good thing since it doesn’t carry grit like oil can. Unfortunately, the starved nature of the waxed pressure point makes for a lot of metal-on-metal grinding which wears the chain at about the same rate as the grinding paste in oil does.

I thought chemistry had nothing to do with this discussion. As to the process, it doesn’t work the way you think it does. There’s no evidence for the process you think is acting here such as a chain heating up over time.