How about millions and millions of words written by native speakers who use "less" with words of one and two syllables?
You seem less and less happy as this thread continues. Oh -- look -- two syllables.
This one is a little less pricey than that one, but both are beyond my budget.
He is less skillful than his brother, but his customer service is so much better.
Really, it could go on and on and on.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.