Wildcard does not seem to be working as expected. Selecting {model_ID}*_* expecting to get chains, unfortunately includes {model_ID} into selection.
Eg.
PyMOL>fetch 2V1Z
PyMOL>split_chains
PyMOL>select chains, 2V1Z
Selector: selection "chains" defined with 2473 atoms.
PyMOL>select chains, 2V1Z_A
Selector: selection "chains" defined with 2473 atoms.
PyMOL>select chains, 2V1Z*
Selector: selection "chains" defined with 4946 atoms.
PyMOL>select chains, 2V1Z*_* **
Selector: selection "chains" defined with 4946 atoms.**
P.S. My version here is 1.7.4, but I have the same issue with 2.0.7.
fixed in svn rev 4190 - will be fixed in Incentive PyMOL 2.2