If you find that you are forced to drop for a considerable distance, and your only concern is to do so as safely as possible (i.e. flow be damned), is a standard roll really the best way?
The roll is great for preserving momentum especially with forward movement, but for a high, straight drop I wonder if it's the ideal thing.
This would only be relevant for true emergencies; I wouldn't suggest training drops at a height that you're unsure of landing safely. But no matter how ninjalike you are, it's really plausible that you can find ourself with no real recourse except to drop, and for those of us who aren't David Belle, landing from something like a 15 foot wall with a squat and a slap may be unlikely.
One possibility I could think of is a parachute landing fall (PLF), which is meant for approximately this same purpose. Any other suggestions are welcome.