A man is having a drink and chatting to the barman. 'I've just read an article about what sort of man makes a good lover,' he says. 'Apparently when it comes to sex, it's not all about size - it's also about thickness.'
'Can you do anything about that?' the barman asks dubiously.
'Yes' the man replies. 'From now on I've decided I'm going to act really dumb.'