Hi Jon,
Thanks for posting this great topic. Seems like the question you are asking is more than hip position. Rather you seem to be asking how tall to get in V2. I've watched 2010 Olympic videos lots to examine just this question & I'm eager to hear other replies. I think the correct answer is a really tall V2 is just one more gear in the transmission to be used when conditions call for it.
Starting with the basic slightly curved back body position for skating & during the middle part of DP, the question can be framed as how much should the slight curve be & what do the hips do when you load the poles? I think the correct answer is get as tall as you can (including high hands) & the hips sink straight down (not back)given the terrain, cadence & speed/power. But those last qualifiers are critical. You spend so much time on steeper terrain that you are forced to do lots of skating from a medium or low crouch w/ high cadence & lower power. But ideally, you'd get really tall as you crest the hill.
A few years ago LEE BOROWSKI did a little contrasting of low & high body (hip) position during skating. If you watch his videos, you realize the differences are subtle.
In coaching, I see lots of intermediate skiers (skate & classic) who can do all the strokes ok but have only do a single version of each. Cadence is one of the bigger ruts I see - only 1 speed - but height is another big one. So by all means learn how to do a tall V2 & where you can make best use of it. The altitude you ski at will play a big role in this choice.