also, no one mentioned that diesels can and do run
just fine on up to 10% gasolene, so even 20% should
not have been an ungodly problem.

I have a 1990 Ford F250 with the 7.3 NA 'Binder engine. It has 22.5:1
compression. The manual says it can run up to 30% gasoline. I have
never tried this, as I am already concerned about the lubricity of my
Calif fuel. I always add a lubricant to the fuel. :-)