As far as Graal dimensions go, a tile is 1. So 0.045 isn't even a single pixels worth... that's not saying much though since like I said, the friction isn't exactly the speed value. It's a factor that is used in determining speed; but what makes this difficult is when the difference between the slowest mount, the Turtle, and the faster mounts is only 0.045, it makes it a bit hard to easily rank their speed. It's not as clean cut as saying Horses have a max speed of 1.5 and Turtle has a max speed of .6.