Anyway, now watching it again I fully appreciate it as a piece of cinema including the black nature of the humour. Nicholas Hope is an incredible actor portraying Bubby and the subtleties of his character admirably. He deserves the highest praise for this performance. One or two aspects in the second half seem artificial (like an ability to understand mentally disabled peoples thoughts)however it serves to develop the end of the story to a pleasant conclusion. It's very well made and directed as well.
I highly recommended it to anyone interested in underground movies, that are also thought-provoking. I also highly recommend that you don't let your kids near this so take any relevant precautions. It'll be worth it because if you don't, there will be side-effects (and I don't mean the innovative method of recording sound that was used).