being a surgeon or scientist needs a lab & peer checks so its highly unlikely that someone can accomplish those skills just by self educating. we live in a world full of leverage & one can utilize internet to learn some skill but being totally self educated specially on internet & having no other point of learning may not be ideal situation. real world application is important & different in many fields, theoretically whats written & how it can be done may turn out to be a different thing. unlike in sports, nobody 'taught' maradonna or pele the skills they had, what they had was pure instinct, skill & prowess of their own. so it differs in every aspect.