Good to see you still looking into this ECE theory. I do think it adds the flexibility to explain mathematically what would otherwise be overlooked or dismissed.
As for driving transformers with modern high power, low internal resistance MOSFETs, when I use IRFB3077's, I can almost always get the ringing effect mentioned in the white paper. In fact, it is extremely difficult to not get it. I can get this effect at various amplitudes with many different cores too, not just ferrite. When large source power capacitors are used with wide high amperage traces on the circuit boards, it appears to me there is a surge current that drives the transformer into saturation for just a brief moment, as though the core simply cannot deal with the initial power density.
With this design, I have to use a snubber circuit and bleed off the reflection into high wattage power resistors to prevent the kickback from destroying the silicon. I've never actually measured the power dissipation of these resistors, but at times they do seem to be at or "possibly" in excess of the total power used by the circuit. Let's just say two 10 watt 1k resistors get smoking hot when only using 24 volts, 1 amp DC for the power supply, while still driving a load on the secondary of the transformer.
So yes Smudge, there is probably something here worth exploring further.
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