Lonewolf_50 - You're right about the Q400 not being susceptible to tailplane stall. Where tailplane stall came into this accident was because the Captain's previous type, the Saab, *was* known for suffering tailplane stall and the question was over whether he reverted to his previous training under pressure.
stepwilk - The last 707 commercial flight in the US was in 1985, but it continued in service abroad until the mid-1990s. BA retired their VC-10s from commercial operations in 1981, which brought the airline career of the type to an end.
The question of the G-ARPI stick pusher dump. From what I've read on the incident, the first push did succeed in raising the airspeed to where the wings were no longer stalled, but the assumption (due to no CVR) had to be that the crew, who were likely dealing with a major pilot incapacitation as well, thought that it was a false push, pulled back on the yoke and dumped the stick push, sealing their fate. While it's not the same incident in many ways I think it's quite relevant here because it was an inexperienced crew* dealing with a suddenly frightening situation and making bad choices as a result.
* - with the exception of the incapacitated Captain