Re: To Slap the Ground or Not
We don't study breakfalls at my level in aikido, we just roll out. Think the higher grades get them though.
Anyway before I started Aikido I practised Judo. We were taught to let our arms slap naturally from a side or back breakfall. The instructor also said that part of the reason for this was to give you something to do with your arms to overcome the instinct to reach back to try to stop the fall and so end up with a broken wrist.
Just my £0.02