So the conclusion is as we thought, right? The notification is generated after clicking on the reply button, and is sent silently together with the post regardless of its content. You can quote anyone, or indeed no one at all, in the actual text and it doesn't change a thing.

It seems so. Did you get notification now? I replied to you but deleted quote.

Yeah, it's generated from the post window generated by clicking a reply button and the notification is only actually sent if that window is used to post. We weren't sure whether the act of clicking the reply button was enough but it turns out it isn't, you have to make the post as well. This means that mass prods are a complete pain in the arse to do...
Sorry, I think my notification will have overwritten yours. D=

Try again now:

Vitek: I don't know, because I'm being an idiot again. But I did the same -- this should be a reply to you.

SirPF: Yeah, it couldn't really work that way -- you'd need javascript or something of that kind to do that, but this seems to be using the good old post method instead. Not that I expected any different, really.

Yes, it really notified me. I think we are done here. Good job. :-)

But it really looks that way because it really needs both things (pressing "reply" and "Post my message" buttons).