You left out an important part of the "Bad Bots" issue; how to find "bad bots" that are spidering your website.
There are 2 ways....
1. Look every day at your access logs (a little tedious to do each day).
or
2. Create a file to catch bad bots.
Here are some links about creating "Bot Traps".
http://www.kloth.net/internet/bottrap.php
http://www.fleiner.com/bots
Bad Bot list and what to do with it:
http://www.javascriptkit.com/howto/htaccess13.shtml
Of course you can find other bad bots to ban......
The overall concept is to set up your robots.txt file correctly. The bad bots are those who do not follow the rules you set up in robots.txt. You could set up a fake diretory and in that directory put in some kind of bot trap. Then in the robots.txt file, put in a rule to disallow that directory. Soooooo.... a bad bot would open the bot trap, which should alert you, the site admin, what happened and who did it. Then you should ban that bot in the .htaccess file.