I would say 2 things:
1) Lack of pressure to be right is pretty big. Closer votes were more common pre-Samoa. Votes have certainly felt less personal in the post-Samoa/HvV world.
2) Jury hiveminding is a lot more extreme in IRL Ponderosa than ours, for w/e reason. Combined with the urge to be "right," everyone has a sense of what games were played and can bias towards that very hard.