I prefer cutting perpendicular to the ground myself (as a homeowner with smaller trees, rather than a pro). However, this video has several problems...The grain of the tree runs up and down the log. Milling boards is always along with the grain. That cross grain animation is misleading, on a very basic concept. After that, you need to block your log up off of the ground so your blade does not cut into the soil as you go through, but this was not shown. It is very important to safety to stabilize the log so it does not move *at all* during the cutting. This was not shown, but it seemed that this was attempted by wedging other logs alongside the one being cut. The problem is, the wedge no longer works once you take your first plank. It needs repositioning each time, not shown, and not recommended. Again, for safety, cut only one plank at a time...this multiple cut method may seem faster, but weakens the stability of the cuts. The last thing you want is the unfinished bulk wobbling, cracking, or baffling under the pressure of its own weight while you are busy cutting. Finally, when you use what looks like a picarron (not a wedge) to separate the planks at the end, you are tearing them apart, not cutting them smoothly...I've gone into detail not to insult, but to inform. There seemed to be serious safety issues with this video and misunderstandings of wood and trees at a very basic level. Please check almost any other video out there on this technique.