I had a similar experience to Wallace and also have disabled the fuel shutoff solenoid. Originally, without the solenoid, I noticed the slight popping when letting off the gas and my motivation to get it working was mainly to improve the gas milage and it did help that by about 10%.
The downside when the solenoid activates and cuts the fuel is that you can feel a noticeable jerk due to additional engine braking. This was really annoying if you are barely on the gas just trying to maintain a low speed in 3rd gear and it kicks on and off. This is because of the two switches on top of US manual transmissions that activate in 3rd or 4th gear only and are in a circuit that activates the solenoid when you completely let off the gas. These are not shown in the regular schematics. I have a special addendum sheet for 1968 that just shows the circuit with the 3 switches.
The clincher for me was figuring out it will sometimes kill the engine when slowing down in 3rd or 4th gear. You can easily roll to a stop with a dead engine, even pushing the clutch in plenty of time.
Technically the design works and achieved something to satisfy the new vehicle regulations that were rolling out in the late 60's, but it is more annoying than its worth in my case, but maybe if you are running rich the fuel in the exhaust is more annoying for you.
The other issue is that solenoid can leak oil. When I disconnected it my oil leak went away.
In any case, just try it for a while, it's certainly easy to disconnect if you dont like it.