I think 0-fee is completely unnecessary. 0-conf is critical.
What if its not real the goal but a way to force a free floating real time market, by taking away the crunch ( on a small # per TX) could that be like taking the training wheels off?
Perhaps. My fear is that 0-fee protocol that isn't adopted by all nodes will cause a much larger probability for double-spends. If there's a way around those concerns, I'm supportive.