"...doing any work to develop them."

I suppose you can guess what my attitude would be to that. I don't consider the comparison to playing the guitar relevant: we know what a guitar is and what 'good' guitar playing sounds like - and a guitar sound can be replicated 'almost' at will. ESP abilities, if they exist, don't work like that and cannot be shared and demonstrated...only referred to and evaluated by hearsay.

In that light, I strongly suspect that much "working to develop them" involves 'believing' until one is convinced that something is happening. Wishful thinking is a very powerful force. People see it in others, but deny it in themselves.

I realize this attitude of mine doesn't disprove anything: it is merely MY way of keeping an open mind and requiring more than 'reports' from others.