Chess players have studied and observed the same plays and patterns thousands of times over. Running through the next possible 5 moves is cheaper for them, because half of them they can already see the moment they see the position.

In a similar way, it is likely that when a programmer looks at a problem proposition (a ticket), the main patterns behind that pop into their mind immediately.

What that affords is overall deeper thought.

The shallow thoughts don't take much mental capacity.

Meanwhile for a novice the opposite is true. Shallow thoughts do take their effective mental capacity, because shallow thoughts ARE deep thoughts.

But the perceived effort is the same.

This is how you get the Dunning Kruger effect.