two points

[Seb via Digitalmars-d-announce]

On Thursday, 9 February 2017 at 20:12:06 UTC, Joseph Rushton 
Wakeling wrote:
> Out of curiosity: is it typical that it would not post until 
> some way into the discussion (as in that example)?  I could see 
> why it would be irritating if it popped up once discussion and 
> review had already started happening.

We enabled it at this point and thus the mention-bot hasn't had a 
comment for this PR.
This was simply the first PR I found.

> Assuming that the bot can be relied on to be 'first responder' 
> to any PR

Yes, It safely be relied on this fact (it uses Vibe.d).
Moreover, the dlang-bot updates its comment on every new PR event.

> I'm happy to try to draft an alternative text for it to post 
> (and maybe also look at what texts it can link to).

Thanks a lot for pushing this!
Let's move this discussion over to the dlang-bot:

https://github.com/dlang-bots/dlang-bot/pull/44