If memory serves me correctly, the main difference is that the reels on the tapes rotated anti-clockwise in the Southern hemisphere due to the Coriolis effect.
As funny as it seems, I am glad nobody thought about it as a true way to prevent cross-zoning like with ridiculous unhelpful initial DVD discs/players Zoning where you could only change your zone 5 times which btw wish someone sue player makers for that.
Its just a matter of reversing the tape content, but I could imagine zoning south versus north hemi, so Australia VHS would not work in Europe :) I mean it would work but you would watch in reverse :)
