Many years ago I worked in a pub in London and he came in most weekdays at 5ish and would have a couple of pints. Always with the same bloke (is he gay?).
Really nice guy I thought.
Fruitcake? No
I think a lot of his conspiracy theories should not be dismissed as nonsense as there is reasonable doubt and some facts that have never been explained.
Some of the stuff he talked about is very interesting and should not be totailly dismissed. However, much of it is not new and has been doing the rounds in conspiracy theory circles for a while.