Wow, lots of perspectives to ponder.
But it did get me thinking!
I have heard that honey is pretty resistance to nasties because the high osmotic pressure it exerts on them. I don't know if that would translate well to dry sugar, but probably wet sugar. Perhaps if I made a really thick solution with sugar and partially fermented wort and let it sit for a few minutes, at room temp, that would be enough to make the solution pretty inhospitable to life. Then add that to the fermenter. No heating required.
That would prevent diluting the wort any more.
It would minimize the chance of infection, if sugar even presents such a risk.
It would dissolve the sugar...whether that's a concern or not.
And I could avoid heating the wort/beer.