DB Tuning disclaimer and/or make tuner configuration more specific to Drupal's usage of MySQL.

I've been thinking about how to improve the tuning calculations to know when to stop. For several of the variables the script will continue to tell you to increase ad infinitum. Unfortunately I think we get to a point where the script can no longer help, you actually need to do some A/B testing to see which is better for your specific situation. Perhaps we should include some sort of disclaimer along these lines.