I couldn't have described this better myself, the only thing I do in addition to this sometimes to help me with the visual if it's just bent a little and giving me grief is to first attach a zip tie to the fork leg and cut and turn it so it barely scrapes the rotor (you'll see why in a moment) and then give the wheel a good spin and lightly touch a Sharpe black pen to the spinning rotor, I hold it against the fork. This is not rocket science, and you will have to wipe your rotor clean after you are through, but you can see exactly where to bend then. The reasons you put the zip tie on is so you don't rub ink on and contaminate your brake pads (unless it's bent so bad that it's rubbing the pads, then get it close first!), and a zip tie is a lot easier to see on the rotor out of the calliper. I clean the rotor with alcohol when I've got it straight. Spin and wipe the rotor off and touch the pen on it again as many times as you need to see, works best if you hit the "high" spot side, but either side of the rotor is fine. I've only ever had to do this three times, but you can get it perfect this way with the visual. It's hard to know where to bend it just going by the sound without any marks on it. I also stick some cloth gaffers tape on the large crecent wrench jaws rather than using a cloth. Your methods and opinions may vary, works well for me.
What an awesome idea. Thanks!