I confess to fast forwarding through much of that video.
In training with RCMSAR, I had the privilege of helming in the biggest waves we can find around here. We were out on a day on which there was a strong wind warning, and we sought the biggest waves. Those were in Georgia Strait, along the side of Valdes Island, just north of Porier Pass. Our boat is a 29' Titan RIB with a pair of Yamaha 225s, with lots of trim adjustment.
The trick is to recognize when your boat is susceptible to "stuffing" the bow, and learn the tricks to avoid that happening. In those waves, 6 to 8 ft, steep and irregular, there weren't any times when I was concerned for the safety of the boat or any of the crew, though it was quite exciting. The best ride is to balance on the crest of the tallest wave, staying there until the wave dies out, then go find another.
Going with the waves is easier, though more dangerous than going into them. That is only a factor of speed, as going downwind you can easily go quite a bit faster than the wave train, but heading into them that is simply not possible.