Each barrel is an individual, with its own "preferences" Some will shoot better fouled, and others when clean. Testing is the only way to find out.
The marks that one sees in factory barrels are most likely from the reaming that is done after the hole is drilled. The very worst are there because the button did not come in contact with the tops of the lands.
Although Savage barrels are button rifled, they are not stress relieved after rifling, nor are they lapped. The lighter contour barrels may also be cold straightened, which can cause shots to walk as a barrel heats.
Some time ago, I met a fellow that had been trying for some time to get a stainless Ruger 77 in .270 to group better. He had done his best to do a careful barrel break in, and was carefully cleaning his barrel quite often after that. I suggested that he start a target, with his clean barrel, and keeping an eye on barrel heat, not clean but keep shooting. After about seven shots, the barrel started to group much better. Since this was a game hunting rifle, that would not see many shots in a typical season, I suggested that he hold off cleaning it till the end of the season, clean it well, and then dirty it up till it started to group at the beginning of the next season, as a part of verifying his scope setting, and preparing for the hunt. He left the range much happier than when he arrived. He had been struggling for some time, and was a careful shooter and reloader, he had just gotten some bad advice.