Ozy,
It's not a prerequisite but are you trying to tell me that YOUR workload will be less if you continue to handfly? Once you have the aircraft "under control" i.e. trimmed, climbing at V2, why would you not want to let the AP take the strain? It will also increase your capacity to then manage the failure with your FO/Capt. Is it a macho thing? Must wrestle the stricken aircraft into the sky?
A4