I don't think the theory is that the muscle memory sequences resemble each other.
Instead, it's that because muscle memory allows you to do things without thinking about it, you can get mixed up about which action you meant to perform and go through the whole process without realizing it.
They're pilots, they do hundreds of stops each year. In case of domestic pilots, even thousands. And with years of experience, switching off fuel control switches is basically muscle memory at this time now.
Instead, it's that because muscle memory allows you to do things without thinking about it, you can get mixed up about which action you meant to perform and go through the whole process without realizing it.