Running over small children in the pool will not make you popular!
Seriously though.... I am spending time unlearning that bad habit where your neck is unconsciously cranked back to look ahead, which can affect the balance of your whole body.
Now I feel my balance is better, I feel ok to raise my eyes or head slightly every few strokes to look ahead a bit. But usually I know if i am catching up behind another swimmer because of the incredibible turbulence they create in the water!