It's a subtle topic, but I think we're often conflating extrapolating from our current mental model with thinking.
Often when I get into a dead end, I realize, all I had to do was to walk my knowledge slower, and try to poke holes at it, flip it backward, toy with it, do games with the problem at point .. it's more of a poetry seeking game than hard thinking. That's why (IMO) most eureka/new solution feels like a loosening, the hard part was going too hard in the wrong direction.
After failing a few too many times you get the habit of not rushing the bad mode of thinking and rather play with ideas.
Often when I get into a dead end, I realize, all I had to do was to walk my knowledge slower, and try to poke holes at it, flip it backward, toy with it, do games with the problem at point .. it's more of a poetry seeking game than hard thinking. That's why (IMO) most eureka/new solution feels like a loosening, the hard part was going too hard in the wrong direction.
After failing a few too many times you get the habit of not rushing the bad mode of thinking and rather play with ideas.
my 2 cents