Your method seems fine. I haven't tried it but I will give it a shot at some point and come back to you. As far as your explanations it doesn't seem too complex, although I can understand people getting a bit scared about the trigonometry (not that it's difficult but people are affraid of numbers and functions).
Most people do play on auto targeting as it's faster and simple. There are some who play with manual but I don't know how many they are.
Anyhow welcome and enjoy your stay
