When Cera and Littlefoot are hiding from Sharptooth inside that forest of thorns(Whatever you want to call it). Littlefoot says "This way." But Cera goes the other way and that leads to Sharptooth chasing after them, and then the battle against Sharptooth and Littlefoot's Mother. Could the narrator be refering to that incident, or not going the right way to the great valley? Or maybe both?
Interesting!

What we don't know is what would have happened in that sharptooth fight if Cera had followed Littlefoot. The results may have been basically exactly the same when everyone escaped the thorns.
I've always been curious about that line from the narrator, too:
"Cera was too proud to admit that she'd gone the wrong way."
It still begs the question to me though: while a straight line is the most direct path to a point in space, it may not be the most efficient. Let's look at how the modern world builds roads through mountains. In many cases, being able to build around the mountain when possible is friendlier to both the drivers and the costs of building the road.
One could argue that Cera's ability to think beyond simply "blindly following the bright circle" and realizing that she could, indeed, go around the rocky, unstable hilly area to get to the same location makes her a 'better leader' in this sense (though she wasn't able to explain this logic to the rest of the Gang so I still wouldn't call her a charasmatic or effective leader); able to react and respond to the situation rather than decide, hey, the sun is this way therefore we have to take a disgustingly difficult route, even though this path may lead around and be much safer.
Littlefoot's route was probably more dangerous than Cera's in the end, especially considering how exhausted everyone was by this point. I would like to argue that Cera made the 'right' decision here after all, not Littlefoot.