Vicky, I cut out a sentence from your thoughtful post:
"Personally, I think any reality is all shared reality, meaning that we all have equal access to it but we choose where we want to be focused."
Maybe "finally" it's all a shared reality, but as you pointed out, normally we're focused on something specific; I'd say to have access to all of reality (or realities) we had to simultaneously focus on all of those realities (putting aside any capacity limits of our minds, this seems still difficult, as we had to have a clue of those realities in order to be able to focus on them), or we had to have no focus at all to be able to have access to everything. A Zen-person maybe would say "focusing on the non-focus".
What Bruce wrote about his retrievals, what I found in my own phasing-trips, and what I've read in other books, there seem to exist personal, private worlds- more or less, as when a retrieval is performed, it is necessarily so that the retriever is able to make a sort of contact to the retrievee, this shows that the retriever is able to intrude into the retrievee's thought-environment. It's an open question if there are personal worlds which are closed off from any access from the outside.
One aspect of what you said is, the interpreter overlay actually can be understood as the builder of personal worlds which in the end have almost nothing to do with the initial trigger brought up by "the perceiver", in Bruces terminology. In those cases, "the interpreter" is our personal creativity; and it can be so very difficult then to realize if we not maybe are living in a self-made up thoughtform world. Although, from what I've read, with some experience one can discern self-created persons from real persons easily, as really "objectively" other persons can surprise one, appear as actually different from oneself, while persons of the own thought-world are more or less boring, as their behaviour is drawn from the own mind; they tell you only what you already know, believe, wondered about etc. but nothing new.
Well, just some thoughts
.
Spooky