I started executing breakfalls as soon as I felt comfortable with my forward and backward rolls. Hooker sensei has "launched" me just about every way possible including koshi nage FROM shiho nage! If you've never experienced this, it throws you over tori's hips while facing backwards. You land face down on the mat! Sounds like fun huh? Actually it is, for me anyway!
Learning proper breakfalls can actually come in handy even off the mat. I was repairing my roof, while starting to decend from the roof I slipped, the ladder fell and I went off the roof backwards with my arms full of tools. I thought I was dead meat for sure! The tools went everywhere, I ended up doing a 3/4 back gainer and wound up with a face full of lawn and no air. Got my wind back and discovered only slight injury to my arms. The funny thing was that I didn't feel tense at all. I was very relaxed the whole time ( up until I met the ground that is! ).
Two and a half important things I would share with someone just starting breakfalls:
1. Find an instructor that knows HOW to "launch" you. This means NOT someone trying to throw you, but rather puts you in such a position that you feel the need to go! This is very important and is, in my opinion, the leading cause of injury doing breakfalls. A good instructor knows when to let go of uke and when to hold on and assist in getting uke "turned" by providing a little lift on uke's support arm (that is, the arm holding tori's gi).
2. Relax into the fall. Don't fight the energy, flow with it. If you're tense, you will anticipate the fall and inevitably hurt something. Relax, flow over and dissipate the energy along the entire side of the body. Never, never land on your spine or back!
1/2. For the guys, don't land from a breakfall with your legs crossed over each other! You should only make this mistake once! It will have your voice an octave or two higher and makes it hard to walk for awhile, not to worry though, it only hurts when you breathe.......! he-he-he!
I train a lot and have taken many, many breakfalls (some even self-induced). I don't recall ever being injured by a breakfall, so I don't understand why people single them out as being dangerous. Breakfalls are done to PREVENT injury. Any ukemi can be dangerous if not executed properly. I think one of the more important aspects is to have confidence in yourself. If you hesitate at all, you'll interrupt the flow which changes the energy and causes incorrect positioning. This is not a good thing! So, find a good instructor, relax, relax harder, relax even harder, did I mention relaxing ?!?!
Dan Pokorny - Mongo