BOAC:
The more the 'system' takes care of the less we 'monitor'.
Shortened approach requiring non standard capture of the G/S from above. Leads to a non stabilized ROD necessitating PL's at idle.
It's hard to mentally put yourself in the exact same situation. But given the scenario, I like to think I would have simply clicked off both the AP and AT. Manually put the aircraft were it needed to be to capture the G/S without over speeding and then re stabilized the aircraft on the approach before re engaging the AP/AT if desired.
A trainee pilot perhaps keen to demonstrate compliance with SOP's that include maximum use of automation, thought otherwise. Something basic got missed, the training captain didn't intervene, and the aircraft consequently ended up in a plowed field short of the runway.
Also, it's not clear from the report, but did the pilot place the PL's at idle to control speed as the ROD was increased to 1400'/min, or was that the AT? Without the failed RA might the aircraft have actually over sped and wouldn't that be what one might expected of a trainee who gets a little behind the aircraft and wouldn't that have been a safer outcome?