Just read a few pages of Keegan about Operation Overlord (Normandy). The British 6th Airbrone Division (not represented in Set II-- boo!) hit their drop points on open pasture and rallied quickly thanks to their experienced pilots.
As for the Screaming Eagles-- inexperienced pilots, "the narrow neck of the Cotentin Peninsula was easy to overshoot and the valley of the Vire was heavily flooded by deliberate defensive inundation." Only 3,000 Screaming Eagles rallied and some roamed for days behind enemy lines while rations and ammo lasted. And there was worse for others-- Some fell into the sea, many drowned in flooded areas and others were scattered by poor navigation or fear of flak, dropped miles from their objectives. The area in which they were scattered was 25 by 15 miles!!!!!
And this wasn't all bad.. because the scattering of the parachutists actually contribued to the confusion and disorientation of the Germans.
Keep in mind this was a night time drop, so there was the great possibility of a miss-drop.
As far as day time drops...
Let's look at what Keegan writes about the German daytime airborne invasion of Crete- the first paratrooper operation in history not supported by ground forces.
After the Luftwaffe's preparatory bombardment, "The Germans had no control over their descent; they jumped from their Junkers 52s, in groups of 12, their parachutes opened by static line... Slipsteam and wind carried them indeed 'like dolls' to their landings..."
Crete's New Zealand defenders knew the assault was coming, as well.
Keegan says "400 of III Battalion, 1st Assault Regiment's 600 men were killed before the first day was out." Many were killed or badly injured by the fall, and many were shot right out of the air. The 3rd parachute Regiment was slaughtered as it arrived directionless, right upon waiting defenders.
So, it would have been great for the game designers to have factored in some kind of possible bad event like a miss-drop or injury
on the stat cards of each paratrooper, depending on the nation and year involved. The Crete invasion was 1941-- and went so poorly Hitler suspended all future airborne operations.
Normandy was in 1944-- by then the British and Americans had had three more years to test out the tactic.
I suppose my proposed house rule will do.... again, the map the game is played on is relatively small... only 1,800 meters long and not even that long wide.. so even if there isn't a mis-drop or some big calamity, a paratrooper wouldn't have to drift very far to land where he isn't supposed to on the maps used in this game. And the enemy forces already deployed on the map would be able to see the paratroopers falling to earth.
Bottom line-- no way could paratroopers land that accurately.