I've been baking brownies (mix, not from scratch) in a metal pan for a long
time. Then recently my girlfriend gave me a glass pan she no longer needed
(same dimension as the metal). I tried brownies in the glass pan and they
came out waaaay better. They were much lighter/fluffier and cooked to the
same consistency all the way through whereas the metal tends to have a hard
"crust" around the outside.

Is this coincidental or are there known advantages of glass over metal?
Thx!