A schedule without links lies
Without links between tasks, a delay does not propagate. The schedule keeps showing achievable dates when they no longer are. Links are what keep it honest.
Without links
New site preparation+3 d Reassembly0 Production trials0unflagged overlap
With links
New site preparation+3 d Reassembly+3 d Production trials+3 d Production restartunchangedthe milestone holds thanks to the buffer
A schedule without links looks like a schedule. The bars are in place, the dates look right. But it does not know that reassembly cannot start before the new site preparation is finished.
What happens when a task slips
In our relocation example, the new site preparation falls 3 days behind. Without links, reassembly keeps its start date. The schedule then shows two overlapping tasks, without flagging it, and a restart date that still holds.
With links, reassembly and production trials slip by 3 days on their own. The schedule shows the truth: the restart milestone only holds because the buffer planned before it absorbs the delay.
Why links get forgotten
- the schedule is built as a list, line after line;
- dates are typed by hand, faster than thinking about dependencies;
- an old file is inherited and never reworked.
A few simple rules
- every task has at least one predecessor and one successor, except the start and the end;
- dates come from links and durations, not from typing;
- an explicit buffer before every important milestone.
It is one of the first checks of the More With Project virtual coach, and the basis of every schedule in Henry.