Hi Mike M.
I'm a little late in this conversation but I thought I would join anyways. I teach both skiing and in-line skating so I'm familiar with both.
I agree with everyone out there pretty much. But- even though they have their similarities, skating is skating, skiing is skiing.....
You asked about rotation and if it is appropriate versus a "ski" turn. You bet. On flats it is a wonderful thing. Something has to generate the momentum and it doesn't always have to be your feet. Watch hockey players. But, do not try it on a hill. Road rash city.... Momentum and gravity will do the trick, no rotation. It will be more similar to a ski turn.
Some people are saying that the cross-over is not great. I have seen it differently. Has anyone seen a person "skid" a turn on in-lines cruising down a hill at top speed? So carving/edging is a must. Also, you get to develop balance and agility. Tight in-line turns through cones are the best!!!
Hockey stops. They are not the same. There is such thing as a lunge stop (1 footed hockey stop where you arc the foot out to the side on a deep inside edge) and a power slide (where you may turn forward to back and slide the skate sideways on a DEEP inside edge.)
If you still have questions, please go to the IISA (International In-Line Skating Association) website at www.iisa.org
where you may be able to find an instructor in your area. Just a thought.