A thought about meditation and dream recall
Those that meditate have probably noticed that "forgotten" dreams can pop into your head when you meditate.
I read a section in a psychology book that said people who learned information under water (meaning with aqualungs and diving equipment etc) would find recalling the learned information was improved when under water again rathern than in other situations (sat at a desk, etc). Perhaps this is one of the reasons why we get fragments - or full memories - of "forgotten" dreams when meditating; the meditation mimics the state we are in when we first wake and recall the last dream.
Also, when meditating, maybe it's not the case that we remember forgotten dreams, but we remember forgotten awakenings from the past? These may have been forgotten because we drifted back to sleep.