Some questions for those who follow the BB facing folklore…
If you screw an external BB bearing in to the BB shell until it just contacts the shell at one point, what is the clearance between the BB bearing and shell at the widest point ?
What is the maximum reduction in thickness of a BB spacer under the compression of normal tightening of the BB bearings ?
If the answer to the first question is less than the answer to the second question, why get the frame faced ?
What is the maximum misalignment allowed for the bearings used in BBs ?
What is the maximum misalignment found on unfaced frames ?
If the answer to the third question is less than the answer to the fourth question, why get the frame faced ?
If cycle manufacturers put a 12 month warranty on their bikes, then why don't they face all BB shells to avoid the inevitable warranty claims for failed BBs?