Redbook layer on SACD - good enough?

"And more important is SACD being played on SACDP sounds lot better than DSD layer to be played on Redbook CDP at the same price range, or even more expensive."

How do you play a DSD layer on a Redbook CDP?

Lafish: I've got SACDP some time before, and then discovered that mastering quality on available SACDs isn't as good as on good CDs (IMO), so I decided to get a good CDP instead. When SACD will be mastering with XRCD quality -then it won.
Kr4: is it common to manufacturers to make CD layer worse then SACD layer intentionally?

yeah, but the existence of the transparent layer could pose a problem for the cd player's optical pickup, no? The cd pickup (780 nm) would have to read through the transparent layer designed for the 650 nm SACD pickup, no? might that affect the sound quality of the transport? I don't know for certain, I am just asking. Or is it totally transparent?

I would imagine this would have been discussed to death on AA.

"is it common to manufacturers to make CD layer worse then SACD layer intentionally?"

Dunno. They have been accused of it but, aside from the DSOTM SACD, I know of no evidence.

KR4-I have the new Miles Davis box set The Complete Jack Johnson-it was mastered using the DSD process but it is NOT a SACD nor hybrid.
So if the information on this is correct then the DSD process can be used to make CD's as well as SACD's.