If I might offer a guess, Fabric-Master, while the name was first seen on the control panel of the 1958 Frigidaire Custom Imperial dryer, was Kenmore's name for their Time-Temp auto dry control. The timer dial, or in some machines like some Kenmore models, a "DRY" button was used to start the drying cycle. While the heat was on, the timer motor was not energized. When the heat cycled off, the timer motor was energized. As the moisture content of the fabrics decreased, less heat was needed to satisfy the operating thermostat so the periods where the heat was on became shorter and the periods with the heat off became longer allowing the timer to advance more quickly toward the end of the auto dry cycle and soon took the machine into the cool down that came just before the dryer turned off.
The Solid State dryness control usually implied an electronic moisture control where fabrics came in contact with a sensor that measured the moisture content of the items being dried. There were several systems and Frigidaire actually used three in one model year, but when the sensors measured that the moisture had decreased to the dryness setting selected, the cycle was put into a cool down and then terminated.
And now, if I might offer a few words of heresy:
The HOH dryers, which I personally consider a step backwards from Maytag's previous perforated drum design in drum size if nothing else, were designed for handling the loads from the original small tub Maytag washers and the electric models on regular vent runs did that pretty well. The previous large perforated drum Maytag dryers won check ratings from CR. The electronic dry control which Maytag introduced, completely leap-frogged the time temp auto dry controls and was the first auto dry system which did not have a propensity, when operating properly, to overdry fabrics. Maytag stuck with the late 1950s dryer design far longer than they should have (not a news flash) and people ran into trouble when they bought larger capacity washers and kept the smaller capacity HOH dryer. That can also be said of the regular capacity GE dryers, but since GE kicked off the washer capacity race with the V-12s, they also should have enlarged their dryer drums sooner, but they were bigger than the HOH drums. It is true that the solid bulkhead WP-made dryers had increased drum sizes and a design that protected the items at the rear of the drum from the incoming heat better than the porcelain drum GE, WH and Frigidaire dryers, but properly installed and loaded with the amount of clothes from a comparable capacity washer, these dryers performed well. In the decade and a half that we had our GE dryer, we never had anything bake onto the back of the drum and it was even used for several years with a 1-18 washer, but neither machine was loaded to capacity and the dryer had a short vent. Another point about the HOH dryer design is that when overloaded, the clothes at the front of the drum were pressed against the hottest part of the drum where the heat entered as they dried and expanded. I like my KA, WP & KM dryers, but I don't think they are necessarily head and shoulders above the GEs, or the Hamilton or the HOH if a proper sized load is put in any of them.
I realize that I have been using dryers since the 1950s and I have earlier and fonder memories of GEs and Frigidaires than other brands. I did not much care for anything Kenmore except the combos. Whirlpool was not that common a brand because WP machines were usually priced higher than comparable machines from Sears. The WP-made dryers with the belt driven blower were noisier than other dryers. I guess from a servicer's viewpoint John likes the fact that WP dryers can take more abuse without being damaged or damaging fabrics. I don't overload my machines so most any dryer that is working properly performs well for me. If I wash something large, like my king mattress pad, I dry it in one of the large drum machines, otherwise I have choices.