"didn’t use×" and "used not√"

[Odessa Dawn]

Q. They didn’t use to allow such goings-on here.
A. didn’t use× used not√. Inelegant form of verb used, though the expression (didn’t use) is frequently used by inelegant speakers.

Inelegant speakers must make up over 90% of the population, then. ‘used not’ sounds odd these days to most people.
More: Gramorak's Blog | A haven for grammar bunnies

I haven’t understood what has been mentioned in the above text thus far because I am not familiar with the word "inelegant" although I have checked the dictionary. As a result, according to the above explanation, what is the difference between the following pairs, please?

I didn’t use to smoke.

I used not to smoke.

[SoothingDave]

Do you know the word "elegant"?

I'm not sure why this author calls this formation "inelegant." As he notes, the "inelegant" formation is the commonly used one.

I would never say "I used not to..."

Maybe it's different in BrE.

[Odessa Dawn]

Happy New Year, Dave!

Do you know the word "elegant"?

inelegant

adjective clumsy, awkward, ungainly, rough, crude, coarse, crass, gauche, uncouth, unrefined, clunky (informal), graceless, uncultivated, unpolished, indelicate, ungraceful

More: inelegant - definition of inelegant by the Free Online Dictionary, Thesaurus and Encyclopedia.

We have multiple synonyms, I couldn’t pick up the appropriate one. However, I would use either awkward or clunky.

[SoothingDave]

I would go more with "unrefined, unpolished, graceless."

[5jj]

I'm not sure why this author calls this formation "inelegant." As he notes, the "inelegant" formation is the commonly used one.

It was not I (as gramorak) who called this structure inelegant. It was the writer I was criticising.

[Tdol]

I haven’t understood what has been mentioned in the above text thus far because I am not familiar with the word "inelegant" although I have checked the dictionary.

Ooooh, get along with you.