I don't see how that changes anything. It just means the homework deadline is 5 days later.
> eliminate zeroes in grade books
Meaning if one does well on the first assignment, the rest of the semester can be ignored. A savvy student, once they achieved an A, will be motivated to not turn in any more assignments or tests.
> and re-do tests
Once you know what is on the test, it isn't really a test anymore.