You may have tried farming ZF but, almost instantly, been dismounted by the first group of mobs you pull - even though you were specced as a tank.
What you want to do to not be dismounted and enjoy the movement speed of a 100% mount is fairly easy.
All you need is a Druid with the Glyph of Travel. This, somehow, doesn't affect a movement speed penalty, as long as you've activated the Travel Form while being out of combat.
Another neat trick - you can pick this glyph up at level 25 and be as fast as any level 40(100% MS) mount.