Presumably, at Crufts, the winner of the Racing/Coursing greyhound bitch and dog are not eligible for best of breed? Do the bitch and dog compete against each other for best Racing/Coursing even?

I don't see why they would not be elegible for BD/BB and BOB -it certainly doesn't say anywhere they are not. I don't think they would pick an overall best of the dog and bitch classes for racers (and no such results are mentioned in last year's results), as they for instance do not pick a best veteran out of the veteran dog and bitch class or a best good citizen.

Yes, as long as they havnt been beaten they would able to challenge the others of their sex, for best of sex(sounds a bit strange writing that..lol). I dont recall the dog & bitch challenging each other in Whippets last year but they have have??

Theoretically you could have the Best of Breed come from the Racing coursing class as any other.