They all use Loctite, even the Leek. Sounds like the OP had poor Torx tools or tool technique, fwiw. I have only stripped Kershaw heads when being sloppy. And Ive disassembled and reassembled Kershaw knives (dozens of models) at least 200 times.
How do you avoid being sloppy? I didn't give it too much thought the first time and it worked fine, second time it wouldn't budge, third time it would, fourth time it wouldn't, fifth time it would, sixth time it wouldn't. That's half and half, one off, one on like clockwork but I wasn't doing anything differently.