sorry,I accidently posted this twice.

Perhaps the reason you forget is so that you can remember.(safely)
I think it protects the new body from reliving the previous death, before the new mind can distinguish
between what is now and what is in the past.
If you remember too thoroughly you may die in sympathy for the previous death.
And children often remember specific things that are usually not dangerous to thier life.
However I have heard of people dieing because they entered into the memory rather than just observing.
It became reality again rather than an incident that was being veiwed from a distance in time.
sometimes dreams and visions can have the same effect.
I have remembered things that way when I was younger.
I would get cuts, bruises, scars and pains in places I know I have never injured in this lifetime.
The memory was so painful that for a moment I could not detach from it.
For me the pain is usually about lonliness,isolation and harshness from those who were around me then.
The scars would sometimes bleed or turn red and full of heat as if they were infected.
They would not go away until I acknowledged them and found a way to forgive myself and others of the pain.
Then they would go away and not return.
Maybe this is why we forget for a while.

Well you got it

not sure if someone posted this,

what about the simple idea that you that was then was ego, based on memories of that life and when you died those memories did too. The parts of you that may somehow transcend the ego into very spiritual experience may be recalled when you enter a very spiritual experience maybe. To me that idea just makes sense and I've had a similar experience. It makes sense to me that what will carry on from your past lives will be something that somehow your actual spirit can register and re-inform this ego and give it that crazy I already know this feeling. So to imagine maybe a situation where you go very very high and are having some mystical experience, you experience non duality and all of a sudden you get this crazy notion of already knowing all this stuff and that you've already been here it's all just feeling so weirrdd. hahaha.  That's the sort of experience I've had however it was drug induced so that changes a lot.

That's exactly what we were talking about...By the time you reach the consciousness you are talking about, you would be detached and more prone to "re-member" whatever happened in the past because it wouldn't hurt you but really expand that new spiritual consciousness...