Your second question always produces a "trigger" in me.
So, would I get a high grade if I posted this same response multiple times, with the words "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum."
The only way to accurately catch these kinds of posts is to have a human read and grade them.
If someone wants simple grading, without reading, simply go into the single item grade book item and give all students the same grade. (I know, you are thinking "but some students didn't say anything," and I would respond with "is the above passage saying something?")