I'm curious about this as well, though I have what seems like almost the opposite problem.

I almost never dream at all, or if I do, the memory fades so fast that even immediately upon waking I am unaware of it. I don't just mean that I forget what my dreams were about, I mean there's no sense of having dreamed at all most nights. I dream perhaps three or four times per month, and remember things from perhaps one in three of those. I've actually been haphazardly training myself in Lucid Dreaming, and of those dreams I remember, I attain Lucidity more often than not.

I've always thought this was a bit strange, since I was able to become moderately accomplished at Lucid Dreaming, but utterly failed to retain memories of dreams much more often than before I started, and training yourself to remember afterwards is supposed to be easier than training yourself to attain Lucidity. What did happen, is I started remembering that I'd dreamed even if I couldn't recall any details or impressions about the dream. It made me wonder if maybe I was dreaming with normal regularity and the memories were just even further out of reach, or if it had actually revealed the full extent of how often I dreamed which was only a few times a month.

Either way it seems like something strange is going on, but if it's the former, then whatever's going on with me is an extreme example of people not remembering their dreams that may be relevant.