80% of the braking is done with the front brake. It's the most efficient and effective braking system of the two. You can learn to use it properly and never have a problem with it. Circuit riders are doing some radical braking.
The problem is, most people grab a handfull of front brake in a wet, slipery or cornering situation. I've found it to be a usuful tool in an emergency situation to drop the bike quickly and avoid a more serious injury. I would rather chance some road rash than splat into the side of a truck or car. If you dress properly for riding, you can minimize that too.
Ako: The older you get, the worse injuiries effect you, the slower you heal and the greater long term impact on the quality of life. I've got some athritic problems in a couple of ares from my dirt bike days that have come back to haunt me and I'm only in my mid-fifties. I look forward to retirement within the next ten years and plan on enjoying them, not riding around on a Rascal. Getting old makes you wiser...