Thanks, though I don't have an issue with understanding how ovens and masonry function....and that's why I disagree with a flue in side the oven, it makes no sense to me at all. Heat will escape the oven chamber faster if the flue is in the oven...period.
When you see masonry structures that are vented like that...inside the fire chamber...they are more like fireplaces, masonry heaters or furnaces, not wood ovens for cooking. I have seen a few vented like that..but they are not efficient.
And, this is not a that big of a deal to fix, especially since the whole front panel isn't bonded to the rest of the bricks of the enclosure. Take that off, install a hearth..which is nice to have...then it's a couple simple arches or straight chase with an angle iron like what's there now.