What's Mallard raving about today?
Sweet Lord, this is going to be a painful week. I mean, I always thought I'd be happy if Mallard went totally bat-shit insane...
Of course we could read this as being an admission that prejudice against homosexuals is one of the last bastions of socially-acceptable prejudice. That's fairly unlikely, but I imagine the rest of the week will be less painful if we all just mentally substitute the metaphoric meaning of fruitcake for the literal meaning whenever Mallard uses it.