@Phaedrux There is a caveat to that advice, which is regarding mixing hot ends such as the Diamond. In such cases, the volume of plastic in the melt chamber is very much greater and can have a significant effect. So my advice for mixing hot ends is to always run the PID tuning with filament loaded. BUT, as you rightly point, this will "cook" any loaded filament, so it is important to purge that out at the end of the the tuning process.