S4P, i agree pros have the same body movement, but (from my standpoint) when i first learned to golf it was by watchnig that and trying to emulate their bodies/hips legs.....

everyone is different, but for me, i had to learn to swing with my arms in the DS..... the turn, weightshift, body all came second. as the reason we move everythng but the arms is to accomodate the correct path of the arms, but all the (direct) power comes from the right arm in the DS. i agree with you that a BS is important (but for a full swing) i think the arms are 75% of the swing and the body is 15% therfore a good BS isn't that important.

if you have the most perfect on plane BS, but if yon don't know how to DS you are screwed..... but most people that have a good DS, have a good BS, but not all that have a good BS have a good DS.

it sounds to me like you are talking about fundamentals (spine angle, tush line) which are always important.