Pensador - how often do I fly with FDs on in manual flight? Quite often. Our SOPs don't allow for flight with FDs off except in the circumstances mentioned and then the FPV is always used. But we always follow the FDs with the PM setting the ACP as directed by the PF. Why? It's because the SOPs are designed with commonality accross the company in mind and the Boeing side has a big influence.
It's not the Airbus way and not somthing I necessarily agree with. We used to be pure Airbus but since being absorbed into a bigger company which took us over we are using their SOPs. However, they do encourage manual flight when the conditions allow and I take the opportunity to do that when I can - and nearly always with manual thrust. They do also not provide for a situation where the FDs could be ignored - and there should be very few. Chris Scott has very aptly highlighted the danger of asking the aircraft to tell you what to do and then ignoring what it is saying.