Medium Mass "rocket Oven" also Vollkornbrot

     I have recently built an earth oven a la Kiko Denzer and am having great fun baking in it. It is a practice oven for me, as I want to start a home bakery and intend to build a bigger oven in the spring. I have also had requests to build a portable oven for catering and festivals. There are inherent difficulties in this. Well, one is they way a ton, literally. Also the clay ovens crack and you need a trailer with really beefed up springs. Also, they use quite a bit of fuel, namely wood, which is not a problem for me as I have a heavily wooded property and am able to cook with trimmings and blown down trees. The biggest problem would be transporting the wood. Also with these oven you have to heat them well above the temperature you need to cook in them and use the oven as they cool through the range in temperatures. This is not a problem for me playing around with the oven at home, but as a business or catering oven there are obvious drawbacks.

    I have also been reading about Rocket ovens. These are a low mass very fuel efficient ovens. They heat quickly and don't need much wood. It would be OK for some uses , but you can't get the results you can from a masonry oven. I have come up with a concept for a compromise "medium mass" oven. It would be the same basic design as the rocket oven, but instead of a steel interior the interior would be lined with quarry tiles. These are only about 1/2" thick or so, much less than the 4-6 inches of typical masonry ovens. I would think they would heat up quicker and the heat could be more controllable as it is constantly fired. It would also have the benefit of cooking in a retained heat oven. not unlike those hearth inserts you can buy. It would also way a lot less ,say 250 +/- lbs. ,and the clay tiles could be inserted on site eliminating the cracking problem. .They're also fairly cheap, so if they did crack I could have a few extra on hand. 

     I have a basic design in mind I could make fairly easily. Has anybody heard of anyone doing something like this? I'm also interested in making Vollkornbrot form 100% rye and sourdough starter. I have a few recipes. The one from Dan Leader is the only one that is 100% rye and sourdough. I have never tried these breads and am interested in anyone's opinion on vollkornbrot.

Thank You.