You have to understand questions like, “Okay, that’s the optimum route, but how much less optimum is this other route?” Here’s an example. It’s a little contrived, but let’s say you’re crossing an ocean, and it’s a dead beat. Now of course it doesn’t matter where you go. Now let’s imagine there’s a 1-degree shift in the grib file. So now the router is going to take you all the way to the corner to take advantage of that 1-degree shift. Now if you didn’t understand what was going on, you’d say, “Okay, I’ve loaded the grib file, I’ve paid all this money for these great programs, and this is the optimum route, so we’ll follow it. But if you understand what’s going on, you’d say, “There’s very steady wind here, the router’s going all the way to the corner for a 1-degree shift, we know that there are 15-degree oscillations in the ocean, there always are, so we know that we’re much better off to hit the shifts up the middle. This is nuts to get yourself hung all the way out there for a 1-degree shift.” So no sensible sailor would do that. But unless you knew why it went out there, you wouldn’t realize that that’s crazy.