Art Hzn - exactly the point to which I alluded. There has to be correct identification and diagnosis before embarking on a course of action. Until experience is gained this is a difficult decision to make and even then many hours may not always be that experience. Indeed recently a couple of incidents make the point.
1. A relatively experienced RAF QFI went around following a heavy-ish landing by a student and was amazed to find damage to the prop of his Grob Tutor. He knew something was wrong downwind when the power settings did not give the expected performance but did not put this down to touching the prop.
2. A student QFI, ex multi engined aircraft, on his 5th conversion trip on a light aircraft found damage to the prop (Tutor again) following a touch and go on the grass runway at Cranwell. He was unaware he had damaged the prop but admitted he thought the engine noise was a bit different on the circuit he flew after touching the ground.