Quite a few phrases in English are constructed like so:
How [adjective] a [noun]…?
This is the question form of the construction, which is often answered with the negative:
Not that [adjective] a [noun].
or the positive:
Quite [adjective] a [noun].
However, from time to time I'll hear the word 'of' inserted before the 'a', e.g.:
Not that [adjective] of a [noun].
This usually sounds wrong to me, with the exception of the case where the adjective 'much' is used. So, this sounds fine to my ear:
Not that much of a problem.
whereas this doesn't:
Not that loud of a noise.
Why is it that 'much' should be used with 'of', and other adjectives not? Is it because 'much' is seen as measuring a quantity (of something), whereas other adjectives that may be used in this construction are seen as measuring the quality of a whole thing?
Best Answer
What about "not that high (of) a fence"? "not that red (of) a heart" "not that smart (of) a person? not that big (of) a problem?
I would argue that if you use the word that to qualify the adjective, the of conveys the meaning of comparison of a specific entity to the class of general entities to which it belongs.
I'm sure the usage can be regional, as well. There is no hard and fast rule.
EDIT
Hey, I did some more research. Dictionary.com has the following usage note for "of" :
So, I suppose that's the reason why adjectives other than "much" combined with "of" sound odd to your ear. I believe "that" can be included with "how" or "too" in this synopsis. Replacing "much" with another adjective occurs occasionally in informal writing and in speech, but isn't unquestionably standard.
When I say these constructions out loud, to me, I often want to insert the of but perhaps that has something more to say about the informality of my speech rather than the correctness of the construction. :)