Just curious, why you put chipping on the tanks, I have seen a couple of interviews with former tankers from WW2 and they mentioned it's one of the things modellers consistently get wrong as they always carried a tin of paint to cover up the chips & wear and tear on a tank. The said it was to keep things as smooth as possible or something like that as they worried that any indent/irregularity would catch a shell and do more damage.
Why I put it on is because I think it adds to the look - its a personal decision as I know others who don't.
While I have not scoured the various books I have looking for evidence to support it, I look at my (wife's) car in sydney's eastern suburbs and see lots of chips on it and she is not pushing it through hedgerows and having small arms ammunition bouncing off - so I think it is not beyond the realms of possibility that they were somewhat worn.
Would love to see any of those interviews as I can't imagine how a paint chip could catch a kinetic round and divert it - but i've only ever played with blanks and never been on a two way range thankfully.