I wonder if there’s anyone on this board that had any knowledge of the process? There were many imitators of the original and many regional processing plants operated by francisees. The method had merit for advance preparation that was clearly suprerior.  Microwave products never achieved the same level no matter how much food science has been applied. The IR ovens cooked very fast and did many sandwiches in 3-5 minutes from a cold start. That’s literally as fast as a microwave.
 
Were the sandwiches flash frozen or just prepared, Doboy flow wrapped , sealed and refrigerated? 
 
What kind of cellophane was used in the wrapping process? It certainly wasn’t airtight from what I remember. This must have been partially critical to the warming process as it simultaneously steamed the bread while cooking, but the residual steam also limited the heat temperature. 
 
Was there something about heating the product in the celophane that today would be cited as producing toxic components that would not been used today and the reason nobody has gone back to it ?
 
I remember two types of IR light ovens besides the hot light/display used to hold already prepared sandwiches for on-demand sales.  One with a drawer and the other had a hinge over cover much like a BBQ (most popular). Both only had a timer and could do about 6 sandwiches at a time. I don’t believe they were capable of convection, but some models I see on the web do have ventilation ports. Any info anyone might know on the ovens? I believe the custom mnfr. of the ovens may have been Welbuilt.
 
There’s home appliances that can emulate this method and institutional products as well. Panasonic’s toaster ovens work on this principle of using IR bulbs above and below to cook and reheat very quickly as others by Cuisinart and Breville. NuWave and clones are sort of doing sort of the same thing with only a top light.