I should probably of clarified that I was talking about the evidence that I put forward was purely anecdotal as I've not conducted any controlled tests and it is purely based upon a old colleagues supposition which I have found true myself in practice. This is probably due to confirmation bias though as through further searching I have not found any real numbers that relate to the tolerances of headtubes and/or headset cups.
I should probably of clarified that I was talking about the evidence that I put forward was purely anecdotal as I've not conducted any controlled tests and it is purely based upon a old colleagues supposition which I have found true myself in practice. This is probably due to confirmation bias though as through further searching I have not found any real numbers that relate to the tolerances of headtubes and/or headset cups.