Fiziwig,
I think this is an extremely important point, and I think the best course is neither complete naivete nor complete cynicism. Roger Woolger addressed this question by saying that the core, emotionally-charged memories are most accurate, and then the edifice of details that people build up around them are more likely to be fabrications. I would add to that, *except* for the case of the person who has a full-sensory flashback experience. Those tend to be near 100% accurate, as Lagrima on this forum will tell you, having verified hers historically.
So, when someone induces memories through hypnosis, say, and they have some memories and impressions but they don't have that full-sensory "you are there" immersion, then what's most likely to be accurate are the strongest emotional memories. What's least likely to be accurate, unfortunately, are the specific details that a researcher may ask for after the emotional experience, like, look at a newspaper and tell me what the date is, what is the name of this or that, etc. etc. Not that these details don't sometimes turn out to be accurate, but they also sometimes turn out to be inaccurate, which leads skeptics to dismiss all of it as cryptoamnesia.
On a personal level, I have been developing my intuition for some 30 years now as part of my spiritual life. I have learned from trial and error what I can trust and what I can't. When it comes to past lives, I trust my sense of *recognition* more than I trust any other aspect of memory. I have trained myself to be extremely honest with myself over this 30 year period. I can see when this sense of recognition is coming from this life, and when it probably isn't. So, I trust that relatively more. I know, for example, when I feel a strong and persistent sense of recognitition for a person I've never met before, and I can tell whether it's coming from a *likeness* to someone I've met in this life, or from a past life, because of the quality of the perception, how persistent it is, and whether it conforms to a certain pattern I've observed in these situations, like the accompanying emotional reaction that doesn't have a cause in this life.
So to summarize, I think this question has to be looked at in shades of grey and not in black-and-white, and it requires rigorous honesty with oneself to discern what one is dealing with, present-life memory or past-life memory.
Steve S.