I just think it's a stretch. Mind you, [b wrote:
if[/b] there were a reason to think "Remedial Chaos Theory" wasn't Abed's imagination, I'd agree that it qualifies.
I think there's every reason to think it IS alternative timelines, not Abed's imagination. Generally, when Abed imagines something, there's a tilt of his head, and he imagines, and then a cut to. Here, as I recall there was no such thing.
Why do you think it's Abed's imagination?