back and fill

verb3

1. •
   To manage a sailing ship so that the wind strikes them alternately in front and behind, in order to keep the ship in the middle of a river or channel while the current or tide carries the vessel against the wind.
2. •
   (figurative) To take opposite positions alternately; to flip-flop

   • Joe found McDowell a vast improvement upon Hagel. Where the latter had backed and filled and referred to his directors, McDowell, to whom responsibility was as the breath of life, decided instantly. — 1911
3. •
   To zigzag, or make a pivot turn by alternately putting the engine in reverse and forward, while turning the wheel or tiller.