Based on my very limited knowledge of the topic, that actually sounds brilliant.
It's my understanding that when a process goes to the background, it forks off, and runs under user id 1, and kills the old process. So, it looks like this is just killing the process under UID 1, and restoring it. That's pretty sweet. Could do that in a script, and then give input to (what I think is) it's STDIN?
Edit: I'll give it a try before decrying it, but it looks like this is merely sending it a "User Defined Signal", and according to wikipedia, dd behaves notably in this manner, and it's unclear what this will do to other applications.