For some reason, I have recently run across several notes about whether bad grammar drives you out of the story.
To which I say: flat-footed style is more likely to do it.
If you write
Bounding about the room, not a single flying spell struck.
that is a dangling modifier, and quite bad because it forces the reader to take a moment to disentangle the meaning of who is bounding about the room. Better that the reader not be jolted out of the story by having to puzzle out the sentence, and therefore better
He bounded about the room, and not a single flying spell struck.
but on the other hand,
Not a single flying spell struck him as he bounded about the room.
is a grammatical but inferior rephrasing, despite the clear meaning, because the bounding came first, and the failure to strike came second. Putting that in the sentence in that order helps the reader by making the subtext support the meaning.
Perfectly grammatical structures can easily confuse meaning, at that.
The wizard, her every footstep making frost form on the ground about her and glitter like diamonds in the light, with regal dignity, swept toward the prisoners.
while technically grammatical, makes it unclear where the adjective phrase hangs its meaning. Better
With regal dignity, the wizard swept toward the prisoners, her every footstep making frost form on the ground about her and glitter like diamonds in the light.
which is still grammatical, but does not put all the modifiers in the middle where they muddle each other. (Leaving one in the middle would also work.)
Again,
The smoke from the explosion settled. Then a monster appeared.
is grammatical, but even if the story is told from the point of view of a character who would describe the scene like that to a third party, that is not what the character would see. The monster would rise up where the explosion had been, or stand revealed as the smoke sank, or even stomp over, or perhaps be teleported in. The art lies in choosing the words and sentence structure that fit the point of view and still convene the scene. (This is why picking point-of-view characters with care is vital.)
And, of course, artfully ungrammatical structures can be useful. Sentence fragments, for instance.
No wizard would entrust another with the final check of his pack. He sat and began going through the pockets. Waybread. Water in a flask, which, if not ever-full, held more water than it seemed to. Rope. Silver dust. Gold dust. Ruby dust.
Grammar is a great aid in ensuring your readers find your meaning as easily as possible. Violating it negligently will only help confuse them.
Bad grammar, punctuation, and unclear sentences are automatic put-downs.
As for danglers, they are put down and minor headache givers. 😂😂😂😂.
Love the reminder that clarity trumps correctness, and that style, not syntax, keeps the reader in the spell.