I'm not sure I get it, but once you moved blocks in a certain run, you can't move them anymore in the later stage, you have to reset the level... The last 2 levels are designed in a way that you (probably) get baited into blocking yourself, so you have to go back and plan ahead... But yeah some parts of the levels, you don't have to do anything else...
Again, maybe I'm not getting what you mean, thanks for the reply !