i dont really know where you were going with that, all i was saying was that the newschool skiing cultuer and rollerblading cultures are the same, and that the majority of the people involved in both (on amatuer and professional levels) are the same.
and skiing has been around for a long ass time, but it was reinvented once in the 40's, once in the late 70's and again in the 90's. as each new wave comes through, the old is looked upon as ancient, gay, and stupid. the newschool skiing culture is young as fuck and, until the last few years, pretty much ignorant of its past.
inline has vert and street, yes, but that only applies to parks. the urban environment is, not on the same magnitude, the same as the outdoor, changing environment that youre talking about. things are different at each spot, you have to watch for cars, cops, security, the risk factor is insanely high. like i said, this isnt on the same magnitude as say, surfing a 40ft wave or ripping an alaskan face, but the similarities are there.
and as for motions: compare park skating (vert, street course) to park skiing. exactly the same, except one's on planks and the other's on wheels. the stance is the same, the basic grinds are the same, the spins are the same. its just the details that are different (more grinding options w/ skates, more air/spinning/grabbing options w/ skis).
that, along with the culture similarities, were the main things i was trying to point out. even though when you get down to specifics the sports are completely different, if you look at the basics, they are the same. they are both products of rebellions against the social norms of the day, and they both tend to ignore the forces that created them, causing them to be hated on by those forces.