When you go into Eye of the Storm battle ground you start on a rock.
Now this rock is high enough up that if you fall you lose half your health or more. I go from about 11k health to 4k odd.
There is a trick to jumping off so you don’t lose any health at all. Im speaking from Alliance Starting point, but It looks like the Horde Rock is of similar structure.
Firstly you don’t need to take the jump ‘slow’ as long as your riding at ‘normal’ riding speed you shouldn’t overshoot.
However.. If you are wearing your riding crop, or have a pally with crusader on you will go too fast and will most likely overshoot unless you are very careful as to the angle you jump at. .
The Trick to Jumping sucessfully is that as soon as your mounts feet hits the Base rock you reverse your direction and jump backward in the direction of the main rock. The best Place I find to jump is the right hand corner of the rock, its slighly lower and the angle is more friendly if you happen to be fast.
While getting off the rock first won’t win you any prizes, and there is fun to be had just to sail off flying towards the ground.. ( and people do like to fall.. just check out the Aldor Lift in Shatt for all the bones.. ) If you can get off the rock with full health your more likely to be of use to the rest of the team. There is no point charging at Fel Reaver Ruins when your only half health,
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Pugnacious Priest's Warcraft Blog 
I just ran out the rock to FR (i’m hordie) and get the little leaf to give me health/mana or just heal myself and drink. It’s enough time until allys come to FR and we smash then :]
I dunno, it’s cool to preserve health on a drop but I REALLY like jumping off of things. Drives my wife crazy because whenever we’re in a high area (like Thunderbluff for example) I have to work really hard to not mount up and take a flying leap.
I dunno what it is, whenever we’re high up I suddenly need to go Lemming.
Levitate off the road doing a dive bomb into Gold Mine in AB dotting on the way down is fun!
Falling Is fun.. running back to body is not..
If you ever want to have lots of fun falling slowfall/levitate off the back of Darnassus’s waterfall, if you survive the fall you will need to hearth out because you land in blue water but it was a gooood long fall..
When I’m on my perky priestess, I actually hit the first towers to specifically heal those people who failed to hit the mid-level rock and instead decided to nosedive off of the starting point. Then I mount up and move to where a dedicated healer would do the most good. “Mobile healinatin’ unit, hooooooo!” as she likes to tell people.
And dropping from the Lumber Mill to the Blacksmith is always awesome. I’ve used that to my advantage so many times that it’s not even funny. I’ll either use my Ornate Spyglass or Mind Vision someone below to see what’s going on and then leap down when it looks like I’m needed. The Spy Glass? Very awesome if you can’t see far or don’t want to waste the mana to Mind Vision someone.