re: Can Fuel Injectors Cancel Out Sub-par Gasoline?

Fuel additives, which I think you're going for, have a few perks, but they are very minimal and don't affect the ethanol content in gas. Differences in gasoline are not that drastic unless you are on the state level, i.e. LA and CA. California uses a lot more ethanol in their gas, E85. Most gas stations get the same make up of gasoline and are required by law to have a certain amount of detergents. Shell and the other big boys claim to have higher amounts of detergents, but their ethanol content is relatively the same.

Additives, when they are useful, only clean fuel lines, injectors, etc. Some boost your octane, minimally.

Fuel stabilizers just keep old gas from separating into gasoline and ethanol, think oil and water separation.