It is also like kid-proofing your house. Don't. The kid will get some bumps and that is how you learn: by failing.
I agree with you; the scrapes and falls are a long-term benefit to the child, but it is rarely a short-term benefit to the parent.
And, if you haven't seen it, this is a great TED talk.
Case in point: My 3 year old knows how to use a screwdriver and can easily find screws around the house to take out and put into things. Yesterday I was, for the first time, wishing I had bought those little electrical outlet cover things.
I went to plug in a 3 prong electrical cord (US style) and it wouldn't go in. I decided to get down on my knees and look into the outlet. Turns out there is a tiny screw driven deep into the ground hole part of one of the outlets. Arrg.. We had to have a talk about that.
Anyway, I still haven't taken the time to go find the breaker for this outlet and proceed to disassemble the faceplate/recepticle to a point to see if I can get the screw out.
Now that I think about it...never mind. She would have most like just taken the outlet kiddy protector/cover plastic thing off anyway, then inserted then screw. After she realized her mistake, she would have most likely replaced the plastic cover. Then, it would have really blown my mind.
Oh well. Smart 3 year old, slow dad.
(BTW, I tried using a high-power neodymium magnet against the screw....but, it looks like the screw is aluminum ...appears to have come from a disassembled HDD.)