Is it ok to make an independent clause into a dependent one with a gerund verb?

I see this particular sentence structure all the time when reading fiction, and it bothers me. I most often see it in between dialogue tags.

1. She whispered, her hair blowing in the wind.

It’s always an independent clause followed by [subject][gerund verb][object/last part of sentence]. I think it’s grammatically incorrect and that it would look better as [independent clause].[separate sentence].:

2. She whispered. Her hair blew in the wind.

Or as [independent clause] as [independent clause].:

3. She whispered as her hair blew in the wind.

Or if the second subject was actually the same as the first, one could do:

4. She whispered, blowing wind through her hair.

I know that the lattermost three examples are grammatically correct, but is the first example grammatically correct? Is it grammatically correct to use [independent clause], [subject][gerund verb][object/last part of sentence]?

Solution 1:

1. She whispered, her hair blowing in the wind.

is not the same as

2. She whispered. Her hair blew in the wind.

The difference lies in the simple form and the continuous form of the verb (or any other “-ing” form)

The simple form indicates an act as a whole; the continuous form indicates an action that was, at the time referred to, incomplete.

The combination of the simple form and the continuous form allows simultaneous actions:

1. She whispered, her hair blowing in the wind. -> She whispered (while/and at the same time) her hair blew/was blowing in the wind.

2. She whispered. Her hair blew in the wind. -> She whispered. She stopped whispering, and then her hair blew in the wind.