Nick Hoffman wrote
Now you are free to have your own interpretation of what formed the gullies but you cannot claim EVIDENCE for water unless it is unambiguous and clear that ONLY water could have left the "evidence".

Alex writes:
I'll reiterate (your anecdote notwithstanding) that you are confusing "evidence" with "proof." The origins of evidence are often subject to multiple interpretations, and in many cases can be claimed to support mutually contradictory assertions. Rather than focusing on the scientific merits of the debate, I feel that this discussion is detouring into epistemology and reaching a point of diminishing returns, so out of respect for you and your work I'll leave you with the last word on the subject. I will, however, see you over at planetary_sciences ;-) G'day.

Alex R. Blackwell
University of Hawaii