A/F/R gauge for tuning

Dale Davies said
I can not remember all the details, but the engine would lay over like it was lean and the plugs confirmed. Jetting, drilling air bleeds or whatever they did had no effect due to the computer correction. Unplugging the fuel solenoid; I have no idea if it would go rich or lean. This was all in the articles documenting the build.
I would have had the articles if my ex weapon had not tossed a bunch of my books and magzines during separation.
My understanding of the Holley replacement was that it was like the Edelbrock Q Jet knockoffs, but it had the feedback feature built in like the original. If they had not modified crap out of the original Q Jet, it probably would have functioned with the shorter Engle cam. Remember that the early EFI systems all had PROM chips which had to be replaced with another with a tune burned on it. PROM; Programmable Read Only Memory. Later came the EEPROM chips; Electronically Eraseable .... These did not perform anywhere like the current flash programmable ECU's in use today.

I'm might not be thinking correctly but here is how I see it.
For this example there is no reversion. Air (oxygen) and fuel are drawn into the cylinder as a rich mixture. Enough to cause a misfire. During this cycle what would be left over is unburned fuel and oxygen. Of the two the o2 sensor only detects oxygen. Oxygen in a higher proportion than if normal combustion had occurred. I think the o2 sensor will read that as lean.
In order for reversion to cause the o2 sensor to read this as a rich mixture it would have to selectively reverse only the unburned fuel past the o2 sensor and none of the unburned oxygen. Diluting the left over oxygen to the point of reading rich.
Again I'm not saying this is right.