First: most delidding now is done through using effectively a vice grip to move the IHS micrometers from side to side until the solder eventually breaks off. If the solder is stubborn you can use a heat gun, but it’s not needed at all. The oven and a razor blade is the early 2010s tech.

Second: the range where a thermal paste is more effective and the range where PTM7950 is more effective are different. The general rule of thumb is that you would use PTM7950 whenever you would want to use Liquid Metal. PTM7950 won’t dry out and is immune to pump out. 7950 will out perform lower quality pastes pretty consistently, but in the case of using it between an IHS and a cold plate on a waterblock a high end thermal paste like KPX or kryonaut extreme will perform better below 80c and 7950 will perform better over 80c.

Ive used Liquid Metal quite a bit in the past and basically replaced every time that I’d use it with PTM7950. If I had a CPU that would sit above 80c I would use PTM7950 on the IHS, but since I don’t need to drain my loop to change thermal paste I’ll stick with that. High end Intel rendering machines or non x3d ryzen 9s would likely benefit if they still sit around the 90c line while hammering the CPU, but that’s my only thing I can think of that it’s out of pure laziness of never wanting to change your thermal paste. And I’m 100% that lazy when it comes to not wanting to take apart my GPU block and repaste it.