They do a lot more when they are very young from what I've noticed. If you lift the hide up to hold them/clean and they are coiled up, when you touch them they should tense up a bit, but after a while I think they get used to you picking them up and don't stay balled up long. Plus I'm sure it just depends on the snake.
They are more timid I believe when they are small/young.
My large female doesn't stay balled long at all when I take her out, but the 2 late 08 ones I just received do for a little while.
My spider does too but she freezes in any position she's in when you touch her.. she's just not normal though haha
Cheers,
Mike