Not sure how your operation works - but in mine - the PIC doesn't have Operational Control. Doesn't mean I can't exert PIC discretion to terminate a flight for a variety of reasons - but using your example above - I can not self-release myself (in an aviation sense!) That dispatch comes from the part of my organization who in my Operations Manual actually states that these few people/designees have 'operational control'. In the end I, as a PIC, can deny a release - as can the Dispatcher even if I think the flight can be made (think of this as 2 to dispatch, 1 to cancel).

At least in my organization, the PIC has certain responsibilities but those don't fall under the actual definition of 'operational control'. In my particular FOM, PIC is not mentioned in any part of the FOM dealing with operational control except in one sentence that eludes to what I said above. No where in OpsSpec A008 which lays out operational control is the PIC mentioned.

IMO, you are confusing PIC responsibilities with actual operational control.