No, it is certainly not. Encoded to CD is most definitely not a no-op.
It's like I said, "Shot in the head, and then tickled with a feather."
Don't tell me that together, it's like being tickled with a feather.
> You realise that's a no-op, right?
Given that the PONO file will have more bits per sample than the CD encoded version, from a digital point of view, no, it is absolutely not a no-op. It has different data in it, even when the reversible compression has been reversed.
If a person with good ears can tell the difference, that's a different question. And even if someone somewhere can tell the difference sometimes, do enough people who pay for music care?
If a person with good ears can tell the difference, I'll give them three lollipops. The record of actual A/B/X testing of such is a pretty consistent "no better than chance".
You realise that's a no-op, right?
I also give you this marvellous study on "golden ears" and "high-resolution audio" versus science: "Audibility of a CD-Standard A/D/A Loop Inserted Into High-Resolution Audio Playback."
http://mixonline.com/recording/mixing/audio_emperors_new_sam...