I started to post a new thread on my approach to tuning with Guzzidiag and Tunerpro. But the more I got into it, the more I felt I needed to explain. So I decided to start with this.
I used to be a pretty fair mechanic (back in the 60s and 70s). I haven't really kept up since I closed my shop in 75, but I did learn a lot from the experience, some of which I hope is still relevant. So here goes my personal rules of thumb (feel free to ignore any or all):
1. Things break when you mess with them: avoid doing more maintenance than needed.
2. If what you did made the bike feel a lot more powerful, it probably isn't.
3. If what you did made the bike feel a lot more powerful, don't worry about #2; just enjoy.
4. Properly calibrated meters and gauges are always better than subjective measurements (e.g., sound, color, feel)
5. The smoother a bike runs, the more powerful it feels.
6. The quieter a bike runs, the more powerful it feels (this includes things like valves and intake noises, not just exhaust).
7. "Everything should be made as simple as possible, but not simpler" Albert Einstein.
8. When contemplating a repair or upgrade, seek as many opinions as possible, but be aware that the majority are probably wrong.
9. The more money an optimist spends, the more value he is likely to feel he received - the opposite is true for pessimists.
10. Whether talking about mechanics, doctors, or just people in general, keep in mind that half of them are below average and average is probably not good enough.
This philosophy has worked for me, so it probably won't work for you (see 8 above).
Anybody have any others to share?