Prior to this doping announcement, I had never heard of this guy, so I have no reason to defend or attack him. Noting that, a couple of thoughts:
First, nothing strange or suspicious in his progression. Looking at those stats (per Tilastopaja), he was primarily running 400 in 2005-2007. Ran several @ 46.xx. Also a 21.81 200. Started running the. 800 in 2008-2009 (just 5 each year), and fully committed to it in 2010. In these 5 seasons, he has been at best a 1:46.xx guy, mostly, with 2 performances faster in 2012: his1:44.98 at Oslo and 1:45.80 in his heat at the EC. Not hard to think of others who have mostly bumped along at one level, but who have a performance or two that are better. (Wheating would be an example.) That's the way it goes for most careers, so nothing weird there for Warburton.
Second: And now he has a doping positive. Assuming that holds up (procedurally, etc.), I do not care much about his statements or his intentions, or how it happened. Were I a personal friend or family member of his, perhaps I would care. As it is, he is the responsible party.