Dreams are about our unresolved emotions from our conscious state of mind. If we do not remember them, perhaps we are finding other ways to deal with these emotions and do not need to dream them into understanding.
When we understand ourselves a bit better, we will find that resolving emotions is just a part of who we are in the conscious state. There is no harm in using the old adage to sleep on it before making a decision. But in most cases it would still be the same decision - right or wrong - because the emotions don't change.