I mean in the case of this guy I have to agree.
He's not 18 years old for christs sake - anyone that ever believed that an 18 year could be faster than all but 2 athletes in the history of the event (and as fast as Sebastian Coe) was deluded and secondly, irrespective of his age (which is probably 23-24) his progression that season was utterly preposterous.
From 1.47.28 in 2011 to 1.41.73 in 2012?!?!?! I challenge anyone to find an example of a PR progression like that over 800 meters at this extremely elite level ever.
Now 'injury'??? He didn't look injured to me in any of his races this season - just consistently beaten by people much better than him.
Couldn't care less that he is out - leaving it more open for the legit guys ^^