Dean Hoffman wrote:

Well, the microwave cooking instructions on a lot of things say to stir halfway
through cooking time. That would lead me to think microwaves have the same
issue as conventional ovens with the evenness factor.

They do. Some microwaves had rotating wave guides hidden above the cooking
chamber in an attempt to even things out. Haven't looked to see if they still do
or just rely on the turntable, which doesn't work all that well. Suspect the
density consistency and evenness of the water content of the item being cooked
is the reason.