Several ways to phrase this question, I suppose: Why concern yourself with your competitor's pace? Why care about what any other runner is doing?
If your fastest time is obtained by running (to use an example) a steady even pace for the whole race, then why don't you do that, REGARDLESS of any slower pace anyone else is running? Why get caught up in a "slow tactical sit-and-kick" race if that is not how you obtain your fastest time?
To be a little more specific. Let's say you are an olympian, your fastest way to cover 5K is by running 62-sec laps for 12:55. So why don't you just do that? Nobody is stopping you. Who cares if the rest of the field is at 12:05 with a lap to go, and then someone sprints out an amazing 52-sec last lap... you still win by 2 secs. And, if someone else runs faster than 12:55, then they win, but you also ran your fastest, giving you the best chance to win.
"The pace was slow". Who cares? You have 2 legs and a brain, can't you run at the pace you want to run?
If you can run 12:55, why subject yourself to running "at a 13:20 tactical race pace", and trying to win, by not running your fastest? It seems to me your best chance of winning any race is by running your fastest.
I'm sure there will be some snarky comments about not knowing what I'm talking about, but let's pose the subject as a graded college term paper: please state the facts and the logic why someone would deliberately run slower than they are able to, and still hope to have their best shot at winning. Evidence, facts, and logic, please.