Well.....I've come to think it depends on the quality of the barrel and the intensity of the round; my 308 (Border barrel) only gets 2 pull throughs with a bore snake when I get it out of the safe, and 2 when i put it back in. Nothing else.
A few months ago, out of curiosity based on the raised eyebrows this 'cleaning regimen' (if you could call it that!) always causes I did a rigorous nitro solvent followed by Forrest copper solvent clean. Virtually nothing came out; 1 black patch then clean, then only the mildest hint of blue on the first copper solvent patch.
The rifle has remained -pre solvent clean and post solvent clean sub-0.25MOA
Does the same apply to my 300win? ....NO!
I reckon that a low intensity round in a superb barrel lets you get away with boresnake only....or maybe I've just been lucky?
PS. I'm always very careful to ensure that the pull-through 550-type cord does not touch the crown at all. The military used to suffer with 'cord-worn' barrels and I'm wary of that [cord-worn, for anyone not familiar, is when day in, day out an individual pulls the rifle through allowing the cord to exit the barrel at an angle. Overtime, if this is done in exactly the same way each time, a cord groove will be abraded in the crown]