The "from the factory into combat" story is AFAIK true, but happened in Stalingrad where the Sovs ditched everything for expediency for obvious reasons. The "Tank Factory" was one of the more contested locales, wasn't it ? I've read the tanks often weren't even fitted with even the simple sights they normally had, and the gunners had to aim through the holes...

The Germans tended to enjoy rather better communications and sighting aids (not to mention training), which resulted in the Soviets trying to compensate by turning tank fights into close-range melees whenever possible. This was naturally a bit of a challenge in itself every now and then on the steppes...