r r r
"Why on earth they were so close to Alpha Max AND Low Height AND Idle Thrust is beyond me".
One guess is that the crew wanted to keep the aircraft in view for a longer time by taking advantage of high AOA protection to slow it down to minimum speed and maintain it/AOA by adding thrust. The computers adjust alpha max to stay below Vs1g stall, may be that slight adjustment was enough to cause a descent from 100ft to 50ft. When pilot decided to go round from twin evils of idle thrust and max angle of attack the aircraft performance was less than desired in the situation. One thing is certain unplanned manuevres at lower altitude is asking for trouble. Perpignan for example.