Common issue in logic based schedule programs.
Example: Say I have a project where I need to install conduit, pull wire, and install devices.
The wire can’t start until the conduit at least starts, and the devices cannot begin installation until we start pulling wire. Of course, the wire cannot finish until the conduit finishes, and the last device cannot be installed until the last of the wire is pulled.
Just using Start-Start does not work because if conduit takes longer, wire and devices are not impacted on the schedule. Nor is anything dependent on those activities.
Just using Finish-Finish doesn’t work because wire might take longer overall than the conduit. Wire would then be shown as starting first.
Finish-Start with a negative lag is similarly flawed as it will not reflect any delay once the successor activity starts.
There are also situations where activity B cannot start until after activity A starts, but activity A cannot finish until activity B finishes.
I can see flagging either of these as warnings, but but they can actually have a purpose.
