This is all very hypothetical so it is hard to say how it might work.
If we take your first alternative, that you don't have access to your
own memories and feelings while reading someone else's mind, I don't
see why it would follow that you would have trouble remembering the
experience afterwards. I may undergo some experience and not access my
memories during it, but that doesn't make it hard for me to remember it
afterwards.
I think you are right that in the second case, you would have a less
accurate picture of the other person's feelings, since your own reactions
might be confused with his. However presumably with practice you could
learn to disentangle the two more easily.
> But, seriously, the ability to _integrate_ multiple sources of
> 'experience' would definitely be needed by an upload with multiple
> robot bodies wandering around the world, and even by someone who is
> just 'jacked into' cyberspace and receiving simultaneous inputs from
> many sources on the Net, let alone a direct mind-link to another
> person.
Sometimes after an intense dream I awaken, and for a few moments it is
hard to reconcile the memories from the dream (which sometimes include
events which supposedly took place before the dream began) with my
real memories. Maybe this experience would be similar to merging two
disjoint sets of memories as you describe.
Hal