good fitting bootsIn my (totally unprofessional) opinion, poor fitting (mostly sloppy) boots is one primarily reason beginners have so much trouble. I love that, steering with rubber bands on your thumbs. (my other totally unprofessional observation is that a lot of people ski with poles that look much too long for them)
Absolutely, a good boot fitter is a must, and I would say those custom foot beds are worth every penny. Once you have that feeling of control, nothing else will do.
I've skied in a variety of boots, have used kotex to take up volume, have taken the liners out and duct taped them tighter and then found Lange, perfect for long skinny feet. When I started getting the custom foot beds (I've actually had to get new ones for each new boot) it was like the sun coming out.
This came up with the girlfriend of a guy I ski with, who is a beginner/low intermediate skier, had bought boots off the shelf from some (probably well intentioned) guy who just sold her her street size boot and that's it. She was struggling, hating skiing. They went home and he took her to a boot fitter, custom bed, the works, and when she came to visit she was a whole new skier (and more fun to ski with).