No, that's not a correct statement either.

I'll try it again.

"I thought that the previous posts to mine might cause someone to report that replacement was needed for all shingles with exposed nails.... "

That is a correct statement.

"obviously this is one exception."

Obviously, but not as stated below:

"If they are covered with roof cement, they aren't exposed!"

Totally incorrect.

The *obvious* "one exception" is that last ridge shingle which must be face nailed with its nails exposed. This is because there is no other shingle to be installed over it, it *is* *the* *last* shingle to be installed.

So, with that "one exception", the nails in *that one shingle* are allowed to be covered with plastic roof cement.

Covering *other* nails in *other* shingles does not constitute them 'not being exposed', they still are, they are exposed out from under a shingle. Those *other* nails in the *other* shingles are exposed, meaning that *those shingles need to be replaced*.

Obviously. (So I thought ... obviously.)