Never never, never spray gasoline! never.
I have many times used propane; but to tell the truth the results are hard to believe. With the fan blowing your propane around you have no control of exactly where it's going.
I won't use ether, also called starting fluid etc; because it quickly washes the oil off the cylinder walls and the compression goes away. Or, by the time you get the ether out, your engine is usually so flooded, that there is little to no oil on the cylinders and same deal; no oil = no pressure.
I don't use carb cleaner, but it's odd that the article would talk about it removing the protective coating,. yet we use it to clean the carb, even soaking it overnight; very odd. I suspect it was written by a tree-hugger.
On occasion, when one of my old cars sits for months, I use a little starting fluid. Am I, inadvertently, harming my engines?
Maybe yes, maybe no.
But there is a better way.
Mix up some premium grade gas,in a 500ml see-thru pop-bottle with 5 to 8% 2-cycle oil, and top it with a dollop of stabilizer.
When you go to start your car, with the battery fully charged, just splash a tablespoon down the primaries, Jump into the car, slam the pedal down about 20/30%, hold it there, and twist the key. Keep the key in crank until the engine is actually running on it it's own; you cannot hurt the starter,it has an over-running clutch on it that can easily handle this. The engine may hit and miss, start popping and finally, as the float bowls fill up, sputter to life.Keep the gas pedal fixed until is hits on all 8 cylinders and starts to rev up uncomfortably, like IDK say 2500 or so. (I do this to make sure all the liquid fuel in the intake gets thru, so that the engine won't flood when I lift). Then ease the throttle back. On my slanty, the fuel pump is a lil weak, and first start in spring, I might have to repeat the fuel splash deal.
To make this go better on my hotrod, I have a tiny funnel that just fits into the Holley's bowl vents. I slosh about 30/40ccs into the front bowl, and another 30/40 in the back. A lil slosh down the primaries, and BadaBoom!, Huston we have lift-off.
That pop-bottle now goes into storage for next time. (I have a place under the hood of my slanty-car for it). The oil in it, replaces that which drained off over time, and whatever got washed off in the first few seconds of cranking. The stabilizer keeps it fresh. My pop-bottle is about IDK 4 years old? maybe older.....
It may sound complicated but this only requires one guy, is not time sensitive, and the results are excellent. And is waaaay easier than using ether. Click, Vroom Vroom.