Lab,
So happens I just did a bunch of "research" into that exact topic, talked to some of the best gunsmiths and barrel makers in the U.S.
Bottom line is - you are not going to get a bottom line. Very strong opiniions on this, ranging from a complete waste of time to absolutely essential.
After distilling a lot of info, I like what Gary Schnieder told me - let the barrel tell you when it is broke-in. Just fire single shots and clean thoroughly after each shot, for carbon and for copper, dry the bore and fire another. Do this until you detect a significant drop in the number of patches required to remove the carbon and also the copper. How many shots will this be. Could be as low as ten or twelve - might never happen with some factory barrels that look like a the rifling machine hic-cupped midway through the process.
I used to shoot ten singles, five doubles and then two or three five-shot groups and call it done. Have some great shooting barrels. Not sure that this is enough for some factory barrels tho.
Good luck. Maybe check the Search area, some info in archives here.