I would have to strongly disagree that the context of the applied method has no relevance..
I'm talking about the FET circuit itself. It doesn't matter that the FET happens to be inside a microphone. The FET circuit design works the same way regardless of what it's attached to.
This mod had come about not because of my knowledge of the technique you describe but purely because of experimentation.
OK, but it's not magic or voodoo. The links I provided show exactly what is happening with the 4.7k mod. The addition of that resistor configures the FET into a textbook example of a source-follower circuit, and the standard math and engineering principles that apply to that circuit also apply when the FET is inside a microphone.
There's lots of information out there about what the source-follower circuit does and how it works. If you're not interested, that's fine but I've seen several technical people discussing this here and maybe one of them can make good use of it. Consider it my contribution to the research.
none of the schematics you show actually show my method
Look at the very first diagram on the rason.org site. That's exactly what the 4.7k mod does, it would be R2 in that schematic.
If it helps you to visualize things, pretend that .1uf cap on the input is the microphone's diaphragm. R1 and the 4.7uf output cap are the standard battery box components.
Joe