Seems to be connected to #4470
Efforts 8, 9, 10 are improved but effort 11 is slightly worse.

Example of file size change in bytes:

-e 8  : 113679 -> 112381
-e 9  : 112477 -> 109950
-e 10 : 108763 -> 107080
-e 11 : 102577 -> 102583