Negative lag or negative float? They are not the same thing
As a general rule, using negative lag is poor practise. any lags used should be there to reflect reality. Genuine situations where activity B cannot start until x days before activity A has finished are few and far between. The vast majority of negative lags around are used becuase the planner is too lazy to split his activities down into enough detail to enable proper FS links with zero lag.
Negative float (generated by using a must finish by constraint at the end of the project when you are running later than the constraint date) can be a useful method of understanding which activities have to be brought forward to recover delay, and by how much. It's a poor relation for those of us who don't have the software to calculate DRAG, and using it this way goes against how CPM and total float were originally intended to be used. -So do so with caution.
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16 years 7 monthsNegative lag or negative
Negative lag or negative float? They are not the same thing
As a general rule, using negative lag is poor practise. any lags used should be there to reflect reality. Genuine situations where activity B cannot start until x days before activity A has finished are few and far between. The vast majority of negative lags around are used becuase the planner is too lazy to split his activities down into enough detail to enable proper FS links with zero lag.
Negative float (generated by using a must finish by constraint at the end of the project when you are running later than the constraint date) can be a useful method of understanding which activities have to be brought forward to recover delay, and by how much. It's a poor relation for those of us who don't have the software to calculate DRAG, and using it this way goes against how CPM and total float were originally intended to be used. -So do so with caution.
Cheers,
G