I would say that if one were to have the attitude of this "cannot" be proven it would make me feel like they were using agnosticism as a misnomer for atheism. Simply because there seems to be a lack of openess to the possibility.
I see your point of view, Edan, but I don't agree. "Atheism" seems to me to mean the total denial of any possibility of the existence of deities - again, without any real evidence. "Strong agnosticism" would seem to me to mean (as I have said) openness to the possibility, but being honest enough to admit that no real evidence exists (at least, none that I'm aware of) and that to believe requires a "leap of faith".
One could also argue - and I tend towards this view myself - that to "believe in" the currently fashionable mechanistic-materialist paradigm requires a similar leap of faith - the faith that our five (or more) senses, augmented by whatever wonderful instruments we can devise, actually gives us a true picture of the Universe. Whatever information we take in via our senses gets organized by our brains into what seems like a surprisingly coherent picture of the "reality" "out there", but, even so, I submit it is impossible to be 100% certain. We could, I suppose, all be living in a vast computer-generated "Matrix"......
The only thing, I would say, that we can be absolutely, 100%, certain of is our own conscious existence. Everything around us could be a very convincing illusion, but there is something
- inside our heads, it seems - that is conscious of the "illusion". Although there are those out there, who call themselves "skeptics" or "rationalists" or "realists" or whatever, who seem to take huge delight in taking even this much away from us. Consciousness, they say, is nothing more than an illusion generated by electrochemical activity in the brain - which prompts the question "Who is the one who is being fooled by the illusion?"
Which brings us, I suppose, to a point of total, all-encompassing, meta-agnosticism; we can't really be certain of anything.
It might be tempting, at this point, to go back to bed, pull the covers over our heads and scream at the universal illusion to "Go away and stop bugging me!!"
But it won't, of course. No matter what we do, the Universe is still out there, and somehow, day by day, hour by hour, we have to deal with it, make use of parts of it, interact with other parts, ignore yet others - but, always, being aware that it might all be a virtual stage set........
Blessed Be, whatever that might mean in the greater scheme of things......