I don’t believe Switzerland should be impassible, but certainly the terrain there made it virtually impossible to move large-scale forces through. Having the Swiss have more units than the other neutrals is a deterrent, but not really correct.
I believe a good representation of the Swiss situation would be:
Switzerland restricted terrain: Because of the mountainous terrain, no power may move more than a single unit into and out of Switzerland in their turn.
The effects of this rule would be obvious. First, whoever attacks into Switzerland violating their neutrality would send a single infantry (as required by rules) to fight the two defending troops. Therefore you could not even capture it in a single move. On your next turn you could send another unit in, or your allies on their turn could also send in a unit.
Eventually you might capture the territory, but even then you could only move a single unit OUT of Switzerland to either attack or join forces fighting in contested territories. Yes you could move one unit in and one unit out on your turn, but that’s it!
This would really represent moving troops through the mountain passes. Face it; Germany had no problem going through neutral Belgium (and Holland was also targeted) to get at the French. If moving troops through Switzerland wasn’t so difficult, they would likely have tried to out flank the French trench lines through there as well.
So now the territory in effect becomes semi-impassible. Its possible to move into, but way more difficult then the other open territories, and powers with large armies will not be able to just roll right over them.
Opinions?
Kim