Out-of-universe: It was kind of an accident. I had the whole 'base commander' in the coat and the helmet and all that and at some point- I want to say it was the picture of looking up at the stars in an X-29's cockpit?- I just doodled up a rat alt so I could post it in my FA gallery. This process repeated several times until I decided I liked the look enough to just give the coat and such to Syd and ruled that they were, in fact, the same person all along. Somehow.

In-universe: probably because he was the only person stupid enough to take a crack at it.