I was just criticized for posting in Requests for Reopen & Undeletion Votes, etc. (volume 01/2015 - ) [current version] without waiting for the reopen review queue process to unfold. Another user commented that he sees no harm in posting a request there. I couldn't find any guidance on this here on meta, and I'd like to hear the community's view.
My own thinking is: As far as I'm aware, there's no way to present arguments in the reopen review queue. If I want to present arguments for reopening the question, the only places I see for doing that are in comments under the question and in this request thread. Of the two, it seems preferable to have a separate discussion about reopening on meta rather than cluttering the question's comment space with it. The request thread says "Please do not use this thread to engage in debates on contentious matters (e.g. reasons for closure)", but I take this to mean that the thread is not for general debate on what should count as reasons for closure, not that it's inappropriate to exchange arguments for and against closure of a specific question. Thus, given that sometimes (often) one needs to present arguments in order to convince others, my take is that it should be possible to post to this thread whenever one feels that doing so might help the community to reach a considered decision on reopening.