HB: but when should such experience be useful? Why listen to it at all?
Such experiences are useful individually to you. It developes your internal landscape, your belief system. As long as it does not conflict with other information, please take it as gospel. The trap is that once you have a "belief", your mind will start to disregard contrary evidence, or discount it as "the exception that proves the rule".
You should listen to these experiences - all of them. They will confirm or conflict with your own experience. You can then evaluate the additional information in refining your own beliefs - strengthening them or weakening them.
These experiences help you determine your vision of and for your life; they are the inspiration for what you will do and how you will act. They will influence your experience of life as a whole.
The distinction here is that your internal world is a different aspect of life than your external world. And that each person has their own internal world.
HB: Don't you think that somebody telling what they saw or what ACTUALLY happened to them has at least some validity?
Yes, but what kind of validity? To what purpose should it be put?
I have had spiritual experiences. What triggered them? Something outside of me? Some biochemical process completely internal to me? If I have an experience, should it be something everyone must have? If I attach a particular meaning to the experience, must everyone that has the same experience come away with the same understanding?
If many people all speak of "seeing God", yet they describe "God" as being different, what are we to make of that?
HB: After all - people are regularly executed and imprisoned on the claims of people saying what happened to them or what they saw. Surely we should require even more rigorous proof in these cases - corroborated by other witnesses to the event or cctv footage.
The law only asks that something be "proven" to a particular degree (depending on the court). I don't think anyone pretends this is a fair or 100% accurate system. It is why some decline jury duty - they cannot imagine being convinced of events, or cannot hold themselves responsible for passing judgment. Having served on juries, it's always a challenge to determine credibility of witnesses, especially when different witnesses either saw things from different angles, saw things with different presumptions, have different levels of observation skills, different levels of understanding, and different recollections.
A recent study suggests that every time we access a memory, the memory is subtly changed.
Old studies suggest that when presented with a visual scene that is wildly outside your expectations that you literally cannot process the informatino into memory.
It is a common discussion point: in the absence of empirical evidence of events (e.g., cctv recordings), should we ever convict a defendent? After all, witnesses are not highly consistent between themselves or over time, and are subject to a variety of external influences.
If eyewitnesses are suspect with external world events, how much more so might someone be when relating an event that is entirely internal to their psyche, entirely subjective?
AS: However, is not personal experience a reasonable guide for development of our OWN beliefs, or should we make EVERY perception rejected unless it can first be made subjectable to laboratory conditions and experimentally confirmed?
A perfect example of the dinstinction between our personal internal landscape and the external world.
And a good reason for maintaining the place of religion as an internal conviction, not something that others must be compelled to accept.