Im leaning more to the go out with everything you have approach, i didnt used to think like until recently.
naturally your going to slow down as the race goes on, but not as much as you think.
if you run the first mile below your previous
PR pace, as sotally tober said, its about hanging on after that. you might get a good kick at the end that will help but you cant plan on that.
also i noticed that when you do start to slow down after running that fast first mile, your not actually going as slow as you think, it feels slow because your not running as fast, but 9 times out of 10 i would say your going faster than you think..
i think im going to wait 2 weeks until the next beach series race to do a 5k but im going to try and fly my first mile, like a 5:30, and then just hang on and see what happens.
you have to also keep in mind that most, not all but most, of the other runners are going to decrease in speed on mile 2 and 3 as well. if your far enough ahead and keep a decent pace going, its going to be tough for anyone to catch you.