I think if one looks at how a loaf of bread bakes conventionally, it is possible to come closer than mentioned in the interview with a microwave.
In it’s most simplistic form two separate but related actions happen when a loaf of bread bakes. The outer surface is dehydrated and browned via non-enzymatic browning. The outside temperature is much hotter than the interior and browning occurs in areas directly exposed to the radiant energy of the oven or the conducted energy of surfaces the outside is in contact with. Because the dehydration happens early in the baking, the outer surface forms a seal that traps moisture inside the loaf. As the interior becomes hotter, the trapped gases expand, and the holes that make bread soft enlarge. Additionally, the gluten proteins denature and cross-link, giving the bread structure.
The common belief that you can’t put metal in a microwave is not totally correct. It’s not wise to put small pieces of metal in a microwave, such as the twist-tie on a plastic bag. Large pieces are another issue. I’ve been putting large stainless-steel bowls in my microwave ever since I worked in a restaurant in Switzerland in 2002 where we regularly warmed items in 2-liter metal bowls. The metal actually acts as a reflector, reflecting radiant energy from the magnetron tube into the food in the bowl. If a bowl material could be found that would absorb some of the radiation, then it may be possible to produce a crust from the bowl, although not on the top surface.
Other issues with a microwave ovens are radiation distribution and cycle time. Conventional microwave ovens use a rotating waveguide and a rotating bottom platform to attempt to distribute the energy evenly. How evenly, I can not really tell, and it seems to vary widely from one oven to the next. Power in the oven is controlled by cycling the magnetron tube on and off. I suspect using a low power with as much off time as on will help even out the heating and create less significant hotspots. One of the reasons bread in a conventional oven bakes the way it does is the heating of the proteins is somewhat limited by heat transfer. This may not be as easy to control with dielectric heating.
It certainly is possible to bake a version of sponge cake in a microwave; there are a number of YouTube videos demonstrating the process. Even in my ancient, low-power microwave oven that lacks a rotating bottom platform, I was able to come up with a tasty, if not attractive gâteau de Savoie au parmesan (http://xrl.us/bpvnwo). I was unable to prevent large bubble from forming due to the unevenness of my oven.