“It may be that there are some who would decry the importance of the rules of natural justice. ……those who take this view do not, I think, do themselves justice. As everybody who has anything to do with the law well knows, the path of the law is strewn with examples of open and shut cases which, somehow, were not: of unanswerable charges which, in the event, were completely answered ; with inexplicable conduct which was fully explained; …….. nor are those with any knowledge of human nature who pause to think for a moment likely to underestimate the feelings of resentment of those who find there is a decision against them as being made without their being afforded any opportunity to influence the course of events…”