Tasks linked with a finish-to-start (FS) link add more time to a project’s duration than tasks linked either with start-to-start (SS) or finish-to-finish (FF) links. These latter two types of links automatically overlap tasks, which tends to decrease the overall project duration. An effective way, then, to decrease the project duration is to look for instances where you can replace FS links with either SS or FF links.
For example, if two tasks can be started at the same time, you can change the task dependency to an SS link. If two tasks can finish at the same time, you can switch to an FF link.
To check and change a task link
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