It’s not just critical thinking skills, it’s also that there’s a big difference between recognition/following instructions, and recall/generating your own memories of an approach. But most students don’t recognize the difference. In other words, “following the route” is a big part of the problem - it doesn’t engage the brain the same and isn’t representative of real world use, and having something explained well doesn’t mean you can in turn explain it well yourself (the more revealing test of internalized true understanding)