The run is taking shape: accuracy {value_pct} at epoch {epoch}, at or within 1% of its best so far.
Epoch {epoch}: accuracy {value_pct}, a change of {delta_pct} points since the previous reading. The run has reached its understanding phase.
Understanding: accuracy {value_pct} at epoch {epoch} — holding at, or within 1% of, the best this run has reached.
