As I understand it the card draw IS the pulse.
I am not the designer but I suppose: Pol air = shattered because it didn't have much of an impact on the campaign but the PIL were good. They fought well in the Battle of Britain. So if Fall Weiss takes longer than a turn the POL airforce can be rebuilt and cause troubles. (After the initial turmoil.)
Correct -- the Polish air force was bombed on the ground and (for game purposes) is out of action at the start of the first turn.
And yes, drawing an event chit is a type of pulse -- one of the 13 types the player can choose (if memory serves).