Often used by ignorant lumberjacks suffering various degrees of hearing loss from using chainsaws on old growth timber.
2. There's no need to shout, old bean.
Often used by Oxford Dons or wearers of jacket sweaters with leather elbow patches (ironically) to gently inform the speaker their volume of speech is uncouthly excessive.
A Die-Hard Who Dat is someone that shows extreme, absolute or complete loyalty for the New Orleans Saints even when they are playing like they did back in the 80's. A Die-Hard Who Dat could also be someone who is a member of The Big Easy Mafia fan club, where "Once You're In..... You're In For Life"
The Superdome is filled with Die-Hard Who Dats. They are the only ones who would show up with them playing like this.