It is possible to base a grade condition on an assignment, but when the condition is evaluated, it appears to rely on the student having made a submission. In most cases, this would be acceptable, but when the student is given a mark without having made a submission (a real possibility), the condition is not seen as completed.

Replication steps:

1. Log in as admin/teacher
2. Create two assignments
3. In the second, create a condition that relies on a grade value in the first
4. Go to the first assignment and mark an assignment without a student submission
5. (I ran cron manually at this point, I'm not certain I needed to)
6. Log in as the student who received the mark
7. Check if the second assignment is accessible
8. Submit a submission to the first assignment
9. (I didn't run cron here)
10. Check if the second assignment is accessible

Expected result: The second assignment should be accessible after the grade is set, even without a student submission

Actual result: The second assignment is not accessible after a grade is set for the first assignment until the student makes a submission