Ok, i will try to explain my idea more.
As i suppose, chance for revolting US are next to zero.
That's because of approx four things.
1.They can revolt only after 1750. That's good considering RL, but game-wise, NA gets colonized much earlier.
2.Easy way to prevent rebellions. Since AI almost always put state religion tolerance to max, and colonies always gets state religions, revolts in colonies almost never happens.
(New Spain happens in about half of my games, but this is because former Aztec (pagan) lands produce a huge rebel armies for often war-exhausted Spain)
which leads to last two issues
3.Low rebel number in NA provinces
Rebel army size depends on three things
a)land tax value-about 6 in required NA provnices, not much
b)city population size-not very large, so to say
c)some is hardcoded, for example Danzig always produce huge rebel armies (which is quite historica,btw)
4.NA land is often disputed between England and Netherlands, and fact that Dutch tend to found TP's, which hardly rebel

. England mostly found colonies, but it doesn't help much.
So i was wondering for some time what can be done with it.
Another question
But since IGC implemented Vinland, i would also like to know how many of you actually turn this option on.