Craggenmore, just because it was being flown manually does not mean that the Alpha-floor would not work. As they were flying level for a long period of time the engines would already have been spooled up at around 50% N1 or something like that.
It does not take 6 to 8 seconds for the engines to spool up to TOGA from that. If you listen on the video you can hear the engines spooling up just as he starts to hit the trees. There is no doubt that he left it too late to hit the power but it was my understanding that he thought the aircraft would do it for him. He also shouldn't have been there in the first place, or as is my understanding.