Perseveration - when continuing the same approach to a solution is wrong

[Strato Incendus]

My level "Check mate" from Pit Lems was considered the hardest level in the pack by nin10doadict when he let's-played it. Nevertheless, the level has remained in a comparatively low position, early in the third of five ranks, because it had one decisive facilitating thing going on: Once you had worked out a particular approach, you could just continue repeating that approach across the entire map to solve the level.


Check mate (Pit Lems, WTF 04)

In contrast, I have just finished creating a level where, after having identified a certain approach, this will get you somewhere - but continuing with this same strategy all the way to the end will cause the level to fail.

This inability to switch strategies and continuing with the old one is also known in psychology as perseveration.

Here is the level in question (replay included in the attachment).


The bee

Solution

The Shimmiers are required to cancel the Bashers mid-slope, much like it's usually done with Walkers.
However, when using this strategy all the way to the end, the pioneer lemming will end up in the left eye of the skull without any possibility of getting back, due to standing on solid ground after having slipped through the ceiling of the Basher tunnel - even though he still needs to create the final connection to the crowd via another Basher tunnel. For that purpose, he needs to turn around.
When cancelling a Basher with a Shimmier or Walker, the lemming will continue to walk up the slope, whereas when cancelling it with a Builder, he will turn around.
At the same time, there aren't enough Builders to cancel all the Bashers with them.
So the first four Bashers need to be cancelled with Shimmiers, the last one however with a Builder, so that the lemming turns around once more.
Instead of reducing the number of Shimmiers to four, though, I've provided a fifth one as a red herring - thus allowing for the perseveration of the Basher-Shimmier strategy, which is required in the beginning, but, if used all the way, will cause the level to fail.

I've explained the solution in the spoiler above, because I'm not certain whether this level is 100% proof at enforcing this yet. That's why I've provided the replay.

I'm pretty sure there are other custom levels also using this strategy to lead the player astray. Can you name any?

Also, maybe our Finnish users might understand the reference this level is making. After all, it's about someone whose name is very closely related to Lemmings...