I had a right London geezer for my AA driving instructor, every now and again he would come out with a very subtle racist comment.
"Have you noticed that everyone who overtook you in the 30 zones today was black."
And he would direct me to let go, or not a car waiting to turn across me depending on the colour of the occupant.
Also failed my first test as his focus got broken into, we had to drive to another AA instructor, with the broken window glass still in the car, and get another focus, only it was a 1.8 derv, I was used to a 1.6 petrol, it was like a rocket ship, and did that thing that diesels do where they pull without any throttle input, very off putting.
Of course my tester was black and the instructor pretty much blamed it on him, and was quite rude to him when he was telling my instructor what I failed on. Although I had the same tester a week later and I did pass, what annoyed me though his mobile went off going round a big busy roundabout near the M1 and I went the wrong way after mishearing his instructions!