Actually his advice is sound in that regard as over cleaning can cause damage. And I agree if it's not a problem no need to mess with it. I'm just curious as to what it is or was myself.
Barrels can be odd, around 8-years ago I had a HK VP-70Z pistol that I bought used for under $200 because it had a pitted barrel. Turned out it shot fine for a service pistol only sold it off because it was about impossible to find magazines for it.
Good luck with your rifle hope it turns out ok.