This is very true, and there are places you must slow down, not that I like to, but it is necessary if you care to stay in the seat. There is also a difference in rough ground with bumps here and there, compared to this washboard ground he is cutting in the video. I run run wide open and take a pretty good bump in stride because of allowing the mower to smooth out before hitting the next rough spot. The washboard affect never gives your mower time to level out, it hits one high spot, goes down, and then immediately goes up on the next high spot. This would give you the ride that is showing in the video, one comparable of riding a bucking horse.