Nope, didn't cross my mind. Should it have? You're burning your onions while caramelizing them, you don't know your shit very well at all. Went back and read your original post, didn't mention anything about liking sugar on the outside too. All you mentioned was you use it to cover up your mistakes.
I do love the irony of adding sugar to cover up your hamfisted attempts to breakdown all the fructose in the onions. Where do you think that sweetness comes from, even after caramelization? There's STILL fructose in there and you just added some more.
Man you are so talking out of your ass, foremost you dont know
howi fry my onions but ill try to explain, maybe if you get your head out of you ass you would understand:
1st im not adding more fructose per se but sucrose, which is a disaccharide made of maltose and fructose.
2nd off all types sugars mentioned which one has the lowest temp to caramelize? educated guess? yes its fructose, so while it gets oxidised and isomerised and what shit all as well, the other sugars stay mostly in place and sweeten as they used to.
3rd caramelization of onions is mostly made to alter the taste to a more "spicy, herb, ripened, whatever" taste by also maillard reactions of proteins.
4th by adding the stable to higher temperature sugar on top of the allready frying / turning dark onions you in fact stabilize / reduce the reactions by altering the cooking point of your pans combined contents. (similar by liquifiyng ice on your walkway by throwing salt / sugar at it).
tl;dr not only did i alter the unwanted fructose to something i like more, no on frigging top of it i mask possible unwanted aroma, and fucking stabilize my frying process long enough to add other raw (for you: cold) ingridients to the pan.
Ill let it rest at that and try to not derail this thread any further.