Mike Raven was a great guitarist. I've seen audiences watch his playing and wonder whether it was worth ever getting their guitars out of their cases again. He had staunch views on what did and did not constitute 'folk', and who festivals should and should not have on their bill. For this reason he could come across as a bit of a grumpy old man at times (and there was no point in debating with him as he 'knew' he was 'right'), but he could also be very kind and humourous. Lots of people I know have found his guitar books helpful. I am sorry he's gone.