That's something I've never heard. I have a fuze which is supposed to have the same specs as the clip, and I've read they have more power then just about any dap. Where can I find more info about Cowon players? I went on a pretty thorough search one day for info on which dap has the highest power output and nowhere did I find info about Cowons outperforming the clip or fuze. For the record my fuze powers my ER4S as well as the leckerton uha6s mkii to my ears, which is the main reason I find your claim surprising.
For what it's worth, the uha-6 on low gain does not give you more power (0db gain). Instead it gives you a cleaner better measuring signal.