All assessments and categories should have a natural weight applied by default.
e.g.
assignment one 75 points - weight = 75%
assignment two 25 points - weight = 25%
Total weight = 100%

If one of the weights is manually altered, then the other assignments should be automatically updated to equal 100%
e.g.
assignment one 75 point - weight manually changed to 80%
assignment two 25 point - weight automatically updated to 20%
Total weight = 100%

We thought that perhaps an additional field could be added to the grade_item table of weightoverride like the demo code has, to determine if a weight was manually changed or not.