I agree with your comments on cost conceptually. The reason that I think it is potentially included in his thinking is because Peter has always tried to find skis for the masses. His skis of the year are always skis that have excellent high end performance but that a solid intermediate can ski and enjoy. His skis of the year always have 10-20-race circled and they generally have icons for green blue and black. Having said this it may be that price did not play as much of a role as Kastle's limited distribution. It would make sense to me that the last thing he wants is to have a ski of the year that only 20% of the people that want to own it can buy it. This of course would augur for both price (expensive) and distrubution (very limited) playing a role.
Personally based upon my summation of his reasons, I think he made the right choice. Anyone that wants the sultan can get it right now for $659. My guess is that anyonne that buys it will like it and it will help their skiing. Hence Peter has a very satisfied custmer. If he gets his/her heart set on the RX 84, then can't find it or finds out that he/she can't afford it, the customer is less satisfied.
And of course not everyone has Phil who offered a great deal on a new hot ski!!