The message
from "Dave Plowman (News)" contains these words:

I'd say he's probably retired from his job as a counter hand at a PM.
Hence the time for all those little jobs for relatives, and the time to
learn up every maker's advertising blurb.

You might be right. There is after all no reason to suppose he actually
told the truth when he claimed to have been a youth in the 60s/70s.

Would account for his interest in the grassy knoll too. These things can
make an impression on a young man.

Didn't make much inpression on me, perhaps I wasn't young enough.

--
Roger