The ability to track the difference between materials estimated for the project (quantities we would put in manually) vs the quantities of materials in the model (grouped).
Currently if you have 8 (qty) 2" tees in schedules, you are unable to subtract that number.
Ideally:
(8 - 2" tees estimated) - (6 - 2" tees in the project) = 2 fewer tees were used (quantity differential.)
or
(4 - 2" tees estimated) - (8 - 2" tees in the project) = -4; (4 more tees were used than expected)