Yes, I have done a 2 day (classic/skate) camp in the Methow Valley in Washington State. Former Olympians as instructors. It was money well spent as I was basically self taught with pointers from concerned onlookers (other skiers) along the way. Go to methowtrails.org for information. The Methow Valley is about 100 miles south of Silver Star, the ski resort featured in the article.
If you’re a very good downhill skiier, you’ll pick up skate skiing pretty fast. Still worth getting a lesson or finding experienced skiiers to ski with though. Like with swimming, you can always improve your technique.