Wow, all the ignorant twits ruined this thread pretty quickly.
First off, Nigel Amos is from Botswana, not Kenya. He has never been coached by Aden.
He hasn't been constantly injured. He did have an injury that took a while to deal with. He may be delicate when it comes to injuries. Anyone with a modicum of insight should be able to see he is what is called a "thoroughbred" or "greyhound" and those types often tend to be injury prone. He has a very thin, fine bone structure. Some of you twits may be familiar with the Swedish study proving thin ankles and calves to be a major advantage in running. You may notice even top sprinters have fine bones and thin ankles. He also appears to have grown a few inches since London. If so he had to deal with "growing into" his new frame.
Will he run 1:41 again? We'll find out. Do you think the year he ran 1:41 in the Olympics, that he opened in March with a 45.94 400m followed by a 1:44.65 the following week? Maybe, but not likely. He is off to a great start this season. But who cares this season has no major championships. Gee, maybe his coach is actually working on his long term development.
It appears many posters here suffer from ADHD with no sense of seasonal development nor year-to-year progression and history. Get a hobby or something.