Don, yes I do think a genuine medium/psychic is either as you mention reading discarnate minds without the deceased person's awareness, or could be connecting to memory held within a database. Could also be interacting with a helpful guide, a playful and/or deceitful spirit or could be actually connecting with the deceased person though I think this to be the least likely. My point in regards to the questions we ask was that a deceased loved one that has moved on most likely can no longer identify with the meaning of such questions and therefore would become confused, unable to answer. Same for those "descending" to a different plane/reality as you mentioned with RB's comments.
There are numerous, even countless planes or realities and as a being moves within these that being's conscious reality as well as its "beingness" changes because the governing physics of each reality can be quite different. Existing in another reality is different than what we would ordinarily think. For example, if here on earth we move to a different country we may be living in a different culture that is unfamiliar to us, yet we are still existing within the same physics/laws of the earth reality. We remember, perhaps even long for home, our friends and loved ones. We don't forget because the earth plane/reality is where our consciousness exists. It's what we know, what we identify with. A being existing on one plane/reality consciously exists within that world and that is what is known to that being. When no longer existing within that reality, under that particular set of governing rules/laws that being has for lack of a better way to explain, become deceased in that reality and is no longer subject to it... again memory of it fades and the being progresses to perhaps exist consciously within another different reality.
I think God allows the consciousness system as well as all individualized consciousness to be as they will be. In other words, I don't think it is God whom restricts or restrains us. I think the laws/rules/constraints of realities/planes of existence are simply one of the aspects in the process of consciousness evolution and yes, perhaps in that we are a part of this system these limitations could be in a sense self-imposed. Hopefully we are all evolving, growing spiritually toward more awareness and understanding. Though I don't think it is possible to know and completely understand everything, it may be a copout as you say to simply accept the position that we are not meant to know certain things. Isn't it our desire to know and understand that fuels us toward betterment? Well, I guess that depends upon our intent, but I get what you're saying.
I don't want to get off on a tangent here, but I find it really annoying when someone says... it's God's will. Granted believing and accepting a situation occurs by believing something is meant to be, however, it also lays responsibility on God rather than taking responsibility for oneself and one's own participation in the situation. More and more I think God allows us to be as we will be. We have the inherent ability to choose, so why would God restrict that in any way?
Well Don, if you ever find a new and improved ES, please do let me know!

Kathy