CWS is a useful mode but one which requires considerable thought and expertise. I used it most often for circling at NCE; I could set the aircraft up and fly it manually but it bought me time to refine my visual picture over my shoulder and on the EHSI or ND, it made small adjustments easy, and needed no button-pushing to enter the final turn etc.
It is NOT an AP mode in the modern sense. For the PF/PM relationship, it’s exactly the same as manual flight (though with the FD available as guidance, not an AP cue which the aircraft will follow).