[gerdesj]

"This sentence no verb."

... is bollocks! Yet, I can see a shimmering phantasm of "has" ... post sentence.

If you are going to create a thing, it needs to be consistent within the framework it tries to describe itself.

A "sentence fragment", whatever that is, needs to be grammatically correct (for a given value of correct) but not simply be a spelling mistake or just plain old bollocks.

I can punch holes into a piece of A4 and call the result "a paper fragment". There is no need to define a term for "paper, useless for printing on".