The tanks crew fire normal rounds too. Just not as often. Really, i dont see big difference here - nearly all types of training could be made with small calibre rounds, and that without much restrictions usually associated to using big 125mm rounds.I dont quite understand what you mean under "offencive engagements"
As i said, to judge USSR/Russia built vehicles we need to look at wars similar enemies. Iraq/Iran war, Indo-Pakistan war, some other smaller wars come as example. Else we could also find many smaller wars where "new" USSR technic obliterated older western technic without much losses. E.g. initial Afganistan invasion, or some even smaller engagements.
I dont think USSR vs Turkey, for example, would be much different than US vs Iraq.