I was wondering since the Breather Baffle sits in the Valve cover and this item is none to get clogged up sometimes if it would be o.k. to pour a quart of MMO down this hole each time I do my oil change, I would obviously be adding my oil through the oil fill cap on the valve cover.

Yes, it is OK to pour MMO down the Breather Baffle hole because it goes directly into the valve cover which then drains into the crankcase.