Gerund as countable?

Hi. I think when you put the an indefinite article "a" or "an" in front of a gerund, I think you are making it countable.

eg,

a tightening of requirements

Do you think we could we apply this to almost all gerunds (like "tightening" - I think this is a gerund) or some gerund phrases like "tightening of money"?

On second thoghts, I think I have never seen the phrase "a writing of a novel" or "a playing of a rough sport." As to the latter phrase, I may have -- I don't know. All confused. Help.