I think that the main "problem" with the beginners moving into intermediates is that you suddenly feel like you loose the taxi dancers: during the beginners stage of dancing, they are promoted as people to ask and get feedback from. Move up to intermediates, and who do you ask when you feel that something isn't quite right?
The teacher? Intimidating, and often hard to catch.
Friends or experianced dancers? why spoil/waist a dance?
Taxis? guilt because they are meant for beginners only.
So people just go and try it on the social dance floor and work things out by trial and error. Is this the best way to practice/learn/iron out the flaws? It's what I do, but it's been a long time since I was a beginner moving into intermediates.
