Note - What I'm aiming at here is sparking a lively 'Mrs Merton-style' debate. It isn't meant as a challenge and I don't wish to cause offence to anyone. With that said, here goes:
To what extent is what you do and teach concerned with keeping traditions alive to pass on to future generations? Are you practicing (and teaching) anything that you know in your heart of hearts you'd never use for real, simply because you feel a responsibility to pass on your chosen style to others? If so, is there any need to do this in the modern, digital age? Let's say I teach a small number of techniques and a student asked for instruction on something else in addition. If there was no-one reasonably near who trained that particular element I'm sure there would be a DVD, book or YouTube clip that covered it. I know that isn't the same as one on one instruction, but if the alternatives were that you either showed them something that you haven't mastered yourself, or simply don't 'feel', then is it such a bad thing?
The old masters only taught what they trained. If they felt that their students would benefit from some form of cross-training then they've point them in the direction of someone else, with a letter of introduction, who could fill out their instruction. Why should we be any different?