There are a bunch of ritualistic practices assorted with cleaning rifle bores and the opinion you get will depend on what works for them. Using corrosive ammunition and using firearms under less than range conditions, required a regular cleaning regimen in the military so a lot of folks adopted that as a standard practice. I have a touch of that myself. One of the reasons is that in my hobby of restoring old rifles, I encounter a lot of really dirty, nasty pitted bores, with hardened cosmolene, and other really obnoxious leftovers from the barrel's military history. Sometimes these shoot surprisingly well but foul quickly-thus necessitating cleaning. I have probably tried most techniques for cleaning from one time to another including electrolysis and I have found that most of them will work but some are more difficult and harder on bores than others.
I suspect though that most firearms with good bores (absent poor conditions, troubled bores, special uses, or firing corrosive ammo) are probably damaged more from excessive cleaning than they benefit. A lot folks probably could get by primarily using the new foaming bore cleaners followed by a quick patch or (gasp) a boresnake run through the barrel, and a quick wipedown with an oily rag, and not suffer for it.
That being said, these are my humble opinions for general cleaning, use a rod sized close to the bore size, don't use a jointed rod except in the field or emergency conditions, clean the rod on a regular basis whether it is carbon fiber, brass, aluminium, or stainless steel. Length depends on whether you clean from the chamber or the bore--cleaning from the bore does not need as long a rod as cleaning from the back of the action will. Either method will work but you need to spend a bit more and get protectors for either the crown if cleaning from the bore or the chamber if cleaning from the rear of the action. Use good quality patches sized for the bore as a finish-cheap ones are fine for solvent use. Throw away out of spec as 243winxb mentioned and also quit using worn bore brushes--these are expendables. Clean your bore brushes from time to time or get rid of them if they become really dirty. Jags seem to clean a bit better for me than loops but to each his own on these. Oh, and buy yourself some brass rods sized close to the bores of your rifles. These come in handy if you need to dislodge bore obstructions cause by sticking cleaning items in the bore or other things like bullets.
One other thing, cleaning is easier if you put the rifle in a cleaning vise that is firmly attached. You can make your own if you are handy with wood working using scraps from Home Depot and the like.
Also a good bore guide is a nice to have.
