The problem of smoke is accurately replicating its use and effect in a wargame.
Laying smoke is the easy part. Moving through smoke is the hard part, bearing in mind if the enemy can’t see through it neither can you.
In a wargame its easy, as the player can see exactly where his troops need to go and just directs them that way, there’s no confusion, no bogging, no going to ground or moving off course because of disorientation, etc.
Obviously sticking to the main road helps but then that’s exactly where the defender is going to bring in fire as well – or has placed his mines!
So, perhaps it was a little harsh on the US player!