It is possible to copy the Base Layer and paste it into itself

1. Create an animator controller and add a state machine to it
2. Inside the state machine have a couple of states connected by a transition, and have the second state transitioning out to Base Layer (Up)
3. Mark all three elements - 2 states Base Layer state, copy and paste in the base layer.
4. This should not be possible as it creates bizzar animation, multiple transitions where there's only one, and also clicking on the state when in play mode influences the order of played states..