That's how I was taught by my native instructor. I messed up a lot of bows trying to figure out what the hell I was doing. I only started measuring things out once I located usable board wood. It is a lot quicker measuring things out. I think on a really wonky stave like the aboriginals here use, you kind of have to adapt as you go into the wood. None of their bows are high performers, but their system isn't as much about performance as accuracy. Short range, long bows, heavy arrows. They actually laughed at me the first time I brought a teak pyramid bow I made that was a sharp and fast shooter to the village. They said it sounded wrong and the arrow went too straight and quick into the target. They kind of sink and drop an arrow into the spot they are aiming at rather than aiming right for a spot due to the low draw weight of their bows and heavy weight of their arrows. In a system like that, you don't need much of a bow, so you don't need much of a plan when making it. Definitely feel and looks primitive when you are finished with one.