I've been pondering whether it would be beneficial to tap some hot air off of the blower, then around the charge of coffee beans and pipe it back into the roast chamber just above the beans.

What I'm wondering is if this would beneficially increase the air temp above the beans and "insulate" the roast, by reducing the air temperature gradient across the beans?

Seems like it would help lower overall MET, which is supposed to be a good thing, yes?

Could also be a horrible idea, and if so I'd like to know why.