The plan will be wrong at least once.
A marathon cycle is too long to assume every week lands cleanly. The useful question is not whether the original plan was smart. It is whether the plan can recover when the runner's life changes.
- Missed long runs need a conservative adjustment, not panic mileage.
- Recovery signals matter more as cumulative fatigue rises.
- Weather can turn a normal run into a stressor that should be accounted for.