I think if your an amateur turner,belonging to a good club that has demo`s and hands on days/evenings you will learn as much as paying for private tuition from a "professional turner",there are so many good club turners,some even world famous turners who give great advice even down to how to hold a tool properly,how to put the right amount of pressure on the tool so you can get a shaving that`s finer than lace after doing roughing cuts with the same tool.I thought I could turn ok till I joined Fairlop woodturners,then I found I was quite bad at it,but after 3/4 yrs there got so much great advice and tuition it made all the difference,I`ve since moved to Norfolk and go to to great clubs up this way,both of which have some really marvelous turners always willing to impart advice and help when it is needed,I do think demonstrators help allot to,as you can pick their brains in the intervals and get advice that way ,apart from getting techniques from them while watching them demonstrate,cheers,
Eric.