Re: One wonders ...
"I've been making money from my knowledge of the PDP11 family since 1979"
It's MY opinion that a virus or trojan on a PDP11 would be hard to insert, depending on how the OS was built/installed. Without a multi-user system and a remote terminal, I'd say IMPOSSIBLE without physical access. And that would be noticed. RT11 *could* be re-built from an operator console, but the reboot of the new kernel would ALSO be noticed, like "reactor scram" due to the reboot (or similar).
You're probably more experienced with these systems than me, so would you concur? Mostly just curious.