My criticism is far stronger than "you can't prove a negative". My own personal experience has provided me with evidence (admittedly not conclusive) that there is some form of higher power at work, regardless of how we attempt to quantify it. The nature of the evidence (dreams, strong intuition, statements expressed without even thinking) is not the sort of thing that can be scientifically measured. However, the simple LACK of a means of repeating something, or even conducting an experiment in the first place, does not mean that the evidence has no value. Logical reasoning is the strongest and most consistent way to form opinions, but anecdotal evidence also tends to be accurate quite often, even if it has a higher probability for error and/or misstatement.

It's as difficult to prove as to prove to a blind man that the Sun exists. Sure, he's heard a lot about it, and you can try to take him outside on a sunny day, but the same feeling can be reproduced by putting him under a heat lamp. He has no reason to believe in the existence of something he himself has no way of measuring. Does this mean that a blind man has reason to say that there is no Sun?

The absurdities that you listed, like the Loch Ness Monster, are obviously different. In the case of the Loch Ness Monster, we know that humans can create fake experiences for others, people can lie and say they saw it, and mistake a simple natural occurrence for the Monster. While one can apply all of these possibilities to some forms of interaction with what we believe to be the Divine, it cannot explain most of the unusual experiences that I have had. Dreams that are told to third party witnesses who can corroborate the telling have then come true. I have witnesses, because otherwise I might be inclined to believe that my recollections of having dreamt something are hallucinations or that the relevance is misstated.

Ask my friend, to whom I said the following in July 2001: "You asked me to tell you if I had any dreams that could affect you and so I just wanted you to know that, on the basis of my dream last night, you should move out of downtown Manhattan because I dreamt there was a major terrorist attack downtown that devastated the whole neighborhood." The very reason he had asked me to warn him about my dreams is because of a whole series of dreams I had told him about prior to this.

I'm far from Pascal's wager and into the territory where my primary focus is to try to understand the how, the why and the implications.