Nothing you have presented discusses any such facts. Except for one enthusiast publication, which you have scorned as a source of information.
Quite true. You would, however, need to read that article to see the experimental conditions under which the tests were conducted.
Huh? Where did I make any such claim. Density has little to do with molecular weight of hydrocarbons, to which I have indeed referred. ONLY A NON-CHEMIST WOULD MAKE THAT MISTAKE. And I don't think I ever made any references to "stability"
Fluff and nonsense. Again, I wasn't discussing "density". Why again are we talking about lighter hydrocarbons?
Your concept of "stability" is a misnomer. What all your physics nerds are describing is the conditions that lead to a flame speed that is accelerated beyond the speed of sound by the reaction rate and the higher pressures under cylinder compression. There is no "stability" issue. The chemical reactions are the exact same as when there is no detonation. The only difference is the speed at which the reaction occurs. Like almost all chemical reactions, it happens faster at higher temperatures and pressure. Each fuel is a chemical, and each chemical will have it's own specific reaction rates for each temperature and pressure involved.
Well for starters, ethanol isn't generally considered "a hydrocarbon", it is an alcohol. As such, it is less energetically inclined to combine with oxygen, since it is already attached to one oxygen molecule.
I did find this: "The octane rating of pure ethanol is 100. What's interesting is that when ethanol is blended with gasoline, it performs as if its octane rating is 112, making ethanol a very effective octane booster when used in gasoline."
What you should also understand is that because it might burn faster than iso-octane, it does not produce as many gas metabolites after burning. Which will have the net effect of not increasing the pressure inside the cylinder as much as other fuels, and it will consequently have a greater resistance to detonation under identical physical conditions as gasoline.
Something to think about:
As you have already pointed out, gasoline is composed of a lot of different chemicals. Lets mix in some water!
Water would have a flame speed of 0, at least until it were dissociated into hydrogen and oxygen. Then it becomes the best rocket fuel known, with a monumentally fast flame speed. And we all know how well water prevents detonation when we add it to the gas tank, so I'd guess it has a pretty damned high octane number as well. Until you "dissociate" that highly stabile water molecule into rocket fuel. I'll bet the octane number of liquid oxygen & hydrogen is in the negative thousands.
Allow me to suggest that much like water, comparing alcohol to other hydrocarbon fuels isn't probably a valid comparison.