1Charlie. I note that you are a PPL so do you have any experience of commercial operations at a busy airfield? The conditions for an aircraft landing behind another are clearly laid down and 99.999% of the time they work OK. The airlines demand high landing rates and ATC works hard to provide them in a safe environment. Inevitably, someone will be slow to clear the runway or not fly precise speeds on final approach resulting in go-arounds. However, when ATC says "Go-around", IMHO only a complete fool would then land. That's because it is only ATC which knows the whole picture and all manner of things are going on which only they know about. I don't recall a pilot landing when told to go-around during my career so it seems to be a fairly rare event.