Gathering in large groups and slowing advancing towards a city isn’t exactly the best military strategy... In this war, or any war. I.E. Sitting ducks make for easy targets.
Make me wander if this was the same military strategy that the Soviets would have deployed take over Europe. Throw thousands of tanks and ground troops towards Europe and watch those countries fold. The US developed tactics and weapons to defeat this. Based upon that it would have been a slaughter of Soviet equipment and personnel.