I only encountered this one time, but it was so significant it stuck in my mind. I have owned a genuine Stronglight crank puller since about 1974, it has the brand and I used it half a dozen times until one day I was pulling a SL crank off some recently acquired frame and found the SL puller did not fit. I tried many times to thread it in and was extra-extra careful not to cross thread but there was no fitting it. Then out of desperation I tried a TA puller (also a tool I had used often before, but only on TA cranks). It fit! I unscrewed it and tried both again several times to make sure I did not hallucinate something but the TA was a "class A" fit on the Stronglight crank and the SL was "no-go", period. So when I put it to the stress-test that TA pulled the SL crank off without a hitch, no threads damaged or even complaining. Make of that what you will, I came away thinking things aren't always as they "should be".