First let’s define the issue, learn to ski and improve, not speed, trees and back country later, no lower leg strength.
.......
In the OP’s case it is about learning a different set of muscles to control the ski and who cares if this is not how the book says to teach, it is about learning and understanding the correct motions, if the ski puts you there so be it.At this point the OP need to learn, practice and ski. Will this be the future ski for what he wants likely not, but they will get him there and help him learn everything he needs to get there. It’s not about speed but control and learning the motions.
I would seriously suggest that the OP PM
@ScotsSkier for his suggestion.
BTW I use my SL’s to practice my turns (GS) at extremely slow speeds because it lets you see and feel your errors with serious consequences.