George is changing the tyre on his small Mercedes, but why? Did he get a puncture? If that is the case isn't the story of George getting a puncture more interesting? That would also mean that he drove home on his spare tyre. Not illegal, but interesting. It's obvious that George knows a) where the spare tyre on a small Mercedes is and b) how to change a tyre because he owns a pair of overalls, or a boiler suit if you will. Why would George have bought a boiler suit if he didn't have the intention to use it now and again?
Lynne asks a perfectly viable question. George however answers a little bit too quickly. He needs to think about a question like that. It's not easy. Anyway, he comes out with 'The Wheel' and, quite frankly, it's a good answer. Lynne on the other hand gets completely the wrong end of the stick. The inventor of the wheel was not stupid. Maybe she has a small point that the inventor of the wheel should have immediately used more than one but if the wheel itself has been invented then it can't be invented again. What she means is that the inventor of the wheel should have had the idea to put 4 together. And what about bikes and trikes? They don't use 4 wheels but they are still perfectly viable methods of transport.
George chases Lynne out of frustration but he'd better go back and check that tyre is on properly. In the space of one conversation he goes from having no wheel to securely fastening it. It looks as though he only secured one bolt before he leaves it. He'll be in for nasty surprise if he drives off for work tomorrow without a firmly secured wheel.