You will never beat farming samsam and stuff in outlands regardless of your mount speed.
Outlands is a transition zone, where they put that there just so you could get to the right level in the 2 1/2 levels you spend there.

You dont go to outlands to farm those herbs which is why he thinks they are so rare. I farmed dreamfoil / sansam and silversage for at least a year in vanilla for raids, if you know the routes its not more then 20 seconds before your on another spawn