If you think of a large project that is late, it is then most likely in crisis/panic mode, as with most things in this mode, the best answer is a half decent plan, simply throwing more resources at a crisis doesn't solve anything other than waste resources and compund the problem.
There is no substitute for scheduling (pronounced shed-uling), planning and decent management.
As with most of these "one liners" or "golden rules", consider them more guidelines (with context) than set in stone.