I'm writing a paper where I'm citing an unpublished paper. It's by a relatively junior author, available on the internet, and it has been already cited, for example, I recently saw a citation to it in a published paper that's already in print for several years (that paper is very well known in the subject matter I'm writing about now - it is unsurprisingly by a far more senior author at a high-ranking institution).
I talked to the author of the unpublished draft a few months ago, and they said that the paper had been under review a couple of times, once in a top journal where it was under review for over a year until eventually the editor decided 'no'. They are now resubmitting this paper for the nth time.
Upon learning this paper is unpublished, my first reaction was to avoid citing it. And I was frustrated with my own initial reaction - was I trying to use my citations strategically (not implausible, see e.g., here) to cite the papers that are deemed "central" in this discussion? Was I not willing to cite because I have often tried to track down, in vain, unpublished papers that are cited in the works of others and I am trying to avoid this frustration in my potential audience?
It is very frustrating. I really admire this paper - it makes a bold, original contribution to the field. I like it better than some of the published stuff on this topic by senior authors. But it cannot become part of the central discussion because the author cannot place the paper in a journal. Since its title was already slightly altered compared to a few years ago (as is clear from the citation I mentioned earlier), the paper does not have a stable "handle" we can conveniently cite. I'm really frustrated that reviewers don't see the merits of this paper and that it still hasn't found a home.
This is not the first time I see an unpublished manuscript that is trail-blazing, read and actually cited frequently, an accomplishment given that the author isn't senior and the paper doesn't have the brand-name tag of a journal at it. Recall that most papers that are published in respectable journals aren't cited. But it's rare that unpublished pieces become central in a debate, even if they are cited sometimes. They can die a slow death by multiple submissions, reincarnated each time to appease the whims of different reviewers until the final piece becomes a lot more intricate, finally get published when the discussion has moved on, or not get published at all and sink into obscurity.
As I was discussing this case on FB, Trent Dougherty remarked that this case illustrates "why it is a good idea to put such papers on the Internet and for us to solidify the practice of citing them in that format. If we keep doing this, circumventing the system could become routine. We don't always need some random referee to tell us what we should read. Peer review includes our own judgment." I think this is exactly right. We should rely on our own judgment when citing and reading, and by citing unpublished papers we can change suboptimal practices tied to prestige, journals, long review times.