Sorry for the preamble here - but I think the context is important.
I'm responsible for tracking progress on a project which runs on a NEC3-ECC contract which requires that programmes (implemented in MS-Project at request of client) be regularly submitted to show the latest progress of works and forecast delivery milestones. The MS-Project files run into 1000's of activities split among 30+ schemes of work each following an identical template.
Some tasks within this programme are constrained by the resource levels available, and the remaining tasks can be safely be assumed to have resource ramp to meet requirements at any given time.
Actual question begins here:
My position is that all tasks where resource is limited to a forecasted amount must be resource levelled (i.e. no overallocations and no significant gaps in the work schedule for each resource), otherwise forecasted delivery milestones are unlikely to be accurate. My reasoning is that these tasks have an assumed duration that has been calculated from the the number of meters of construction to be completed within the task divided by the expected productivity of a single gang, therefore any overallocations invalidate the assumed duration of the task. Similarly any unexplained gaps in in the work schedule of each resource also invalidate the programme, as we wouldn't be standing construction teams down without a good reason.
All this said, I have had several co-workers insist that resource levelling isn't necessary for the programmes we submit, with their explanation being that:
The resource situation is always fluid and as such doesn't need to be modelled accurately in the programme (this is pretty spurious to me, as this is the entire point of setting a status date when updating a programme/project, dates are forecasted beyond this 'line in the sand' given what information is available at the time).
It's too much work to implement the resource levelling (with my response being that while it is labour intensive to level resource for 100's of tasks alongside all other constraints such as work permits from local authorities, geographic considerations, and build sequence dependencies between schemes in the programme; these programmes simply aren't a worthwhile exercise unless resource constraints have been properly factored in).
Am I correct to assert that resource levelling is necessary in the above scenario? If so, is there any literature out there which I can use to back up my assertion? These co-workers are unlikely to take my word for it.
Sorry for how long winded this was, afraid I can't figure out how to express this more concisely. Any thoughts appreciated.