^^^ I too have NEVER seen this conductivity in action in REAL life, during My fairly long time with PC's ,and PC components.
As an example, when EVER I buy a new GPU, I make a point of replacing the thermal paste put on during manufacturing, since I am certainly as capable as the person/machine who did it in the factory, except I have the luxury of taking My time, and doing it as right as it can be done, and the Most recent time I did it, was with My 7870Ghz from Diamond ,(normally I find the white type of TIM, but this time it was silver/Grey, and I would have guessed it was AS5 if I had to hazard a guess.) When I removed the shroud, the die was COMPLETELY covered with TIM.
.and the card functioned fine, there was even TIM outside of the square chip area,on the bare PCB(and even lines of it running inches across the board in hair like lines). I wouldn't say it was a myth personally, but I wouldn't lose any sleep over it either. If it was a common occurrence, I would have come across it by now. and as far as TIM brand quality, AS5 has ALWAYS treated Me VERY well, and I have had MANY more opportunities than the average enthusiast to put it to the test.My 7870 idles @ 28C with a reference blower cooler, and peaks @ around 65C(after I replaced the TIM). MY 2500k is MUCH lower, since it is on an H-70 AIO loop.mid to low 20's idle, and peaking @ around 60'ish.
like this