> city streets with stoplights on each corner. I used to think about this because my commute strongly resembled it. My model was, - Signals alternate in the t

> city streets with stoplights on each corner. I used to think about this because my commute strongly resembled it. My model was, - Signals alternate in the two major directions, - Lights always last the same amount of time, - No phasing correlations, and - Some assumption about crossing time and signal length I can't remember. Might not matter, probably simplest to model it as "crossing takes no time, one or the other direction is always green." Under those assumptions you want to stay close to the diagonal. If you end up on an edge you'll have to wait at most lights, but if you're on the inside you can always cross in one or the other direction. Sometimes it's worth waiting to cross if it'll keep you closer to the diagonal, but I don't know that I ever say down and worked out when, and how long you should be willing to wait if there are countdown clocks.