Ken is a sound fellow and his lens tests are a useful guide. Not the last word, but useful. If he says a lens is a piece of scrap plastic best left in a bargain bin at a discount photography warehouse then it probably isn't all that great, and if he says it is the best piece of glass he's ever used, it's probably worth investigating.
However, I cannot find any reconciliation with his statement "I couldn't hear anything different after several hours of careful listening, much less better or worse, between a 25-pound dedicated CD player and the same CD played out of my iPod Touch 4G as coded and compressed via iTunes..."
In this case I will stick with my experience, and cast Ken's findings into a dark corner.
I heard an ipod on a docking station attached to a decent system at a Manchester hifi show a couple of years ago. Nobody had a bad word for it, many even commented how well it sounded. My ipod classic has a very revealing and musical sound through some Sennheisser £20 earbuds.