Yes its mechanically hard for someone to go fast when it comes to double bass playing, but I'd rather go for a simple syncopated foot pattern than play 160 beats per minute. And thats why I try to put some effort in practicing rudiments with the feet, coz it somehow helps in strengthening your weaker foot, and it make you more familiar with unusual foot patterns.
Jason Bittner said that it took 20 years to get where he is now regarding footwork.