Thanks for posting the video. This method would be really good for flattening a lot of boo at one time, or at least getting ready for fine tuning with a hand plane.
I think a lot of people, especially the inexperienced can make mistakes being in too much of a hurry, or trying to bring it to a finished level, with a coarse tool(eg a powered plane).
The best approach is covered in Dean Torges video, about the bamboo backed bow. There is more than one way to skin a cat, and they will all get you to a piece that is ready to glue onto a stave. Not all methods are equal, or as elegant as Dean's approach. Dean"s video covers what you do, and why you do it. Lots of little tips and tweaks, templates, so you can avoid pitfalls and inelegant design.
All quick methods run a high risk of ruining material, especially if you are inexperienced.
Labour intensive methods like hand planing(no power) will get you there, but there is much less risk ruining material.
The best approach is to remove waste, and flatten with power tools(bandsaw, or jointer, belt sander or electric plane) keep slightly oversized. Fine tune with sharp hand planes, just before glue up.