Oh no, that's exactly what I was getting at. That's a possibility: it would just involve making a database of every whois initiated (let's say you're on a client that operates on multiple servers and could whois multiple people simultaneously). Is it a lot of work? Maybe not. It just seems a bit excessive for a silly timestamp. Plus, the benefits of implementing the entire suggestion would be a definite bonus.
Edit: I knew there was something I forgot to add: the scripting method would only work properly for /whoises initiated by the user. If a /whois was initiated by a script, it may not operate properly (for example, one could not simply "default" to the status window if the single message window is open, in which case the target could be either). If it weren't really nebulous, trust me, I'd try to script it.
