I like my term for this "Resource Referencing" - I think it is better because there is never enough time, what do you think of this method?
This method consists of using P6 data columns for quantity and rate and unit. That basically turns the schedule into an excel spreadsheet. For example for track, we simply want to know how much track per activity and the Total should add to the Total for the Project, very simple. 1 items per activity – for the major items, no doorknobs etc. I have seen similar jobs where they put in a text column like 500/lf day etc – but it is much better and easier to balance using a integer to data column. In fact I would put in a Total and percent and for some of the items I would just have it calc an estimated quantity based on what percent that area was. That way if you have to estimate to get it to balance you can use global commands to paint the data a bit, say increase all conduit quantities by 10% etc. But you probably would not have to, there is probably some spreadsheets on your end with breakdowns. Being that these are all cad sheets, the computers breakdown the quantities pretty easily.
For Volumes of Work and Productivities be considered in Monte Carlo as non-deterministic parameters activity durations must be driven by non-deterministic resource/crew production rates and resources must be leveled on each iteration.
It can be argued that it is assignments productivity the parameter that best define the correlation among activities.
Resource referencing is only for information purposes and cannot be used for reporting, analysis and other meaningful functioned of resource loading. You cannot do resource leveling in resource referencing. You cannot prepare S-Curve and other meaningful report. You cannot do risk performance and analysis...etc.