I do not disagree with the geometry. But I do say that as long as there is not 1/4" (.250") of wander to the bore within 26" in the end it may not matter much to even the very best shooters/bullets/rifles/shooting types.
Only a blind test would really show any difference...except every barrel is an individual. The guy at Sierra that tests their bullets has done some blind tests on stuff like Cryo treating....with say 8 barrels in the test, all of same mfg...and 4 done the easy way, and 4 the hard way...the data would show if a shooter using matchhkings and other off the shelf bullets could ever discern the difference. My guess is "nope".
Bill