Here is a photo from Bob Bravier's book "Keys to Racing Success" (1981). It shows something that I always thought was a great idea: using guidelines painted or taped onto the deck to help when tacking, and also a "mast abeam helmsman" line across the cockpit. You can also see two stopwatches on his wrist, a course plotter of some sort, and a calculator. Down where I sail on the Gulf Coast, nobody seems to use such things on Sunfish, BUT back when I did a lot of bigger boat racing a few years ago it was not uncommon to paint guidelines on your deck to show how tight to trim the jib, where optimum mainsheet trim was achieved and so forth. And we all used course calculators, plotting boards and stopwatches.
So.... here's my question: Do you think lines like that would be helpful on a Sunfish? Obviously it worked for the guy in the picture, since he was one of the more successful racers in the 1970's. One of my friends thinks it would be "operator overload" to use it, and believes "flying by the seat of your pants" is better. I'm not so sure. What do you think?