It is difficult to say but If I were the trader I will definitely keep holding then look for more money to buy more Bitcoin. This always works for me and it's fun to do! If the price falls again, you look for more money and buy more Bitcoin. If it falls again, you buy more.
Then if price begins to rise, you start selling off the dips you bought bit by bit until you are left with the main holding which should be your long-term holding.
If i get you right, you mean you always introduce more fiat to buy more dips and sell off when it rises to cash out your fiat while the initial purchase which is the main holding will be the one to hold for long term???
It makes sense to some extent as it is possible one can re-coup the initial investment via that means.