Half the information on CDs is analogue

In some sense that idea is correct.
The pits and lands edges are created by a mechanical process (or in the case of a digital copy, by a laser)
and are subject to ANALOG style errors. Also the pits and lands are read by a device taht travels in an analog manner past the pits and lands.
This is usually called 'jitter'.
Beyond taht, sounds sort of 'mystical'?? What sort of other analog information are you trying to pull out?

The pits only serve to provide digital iformation which requires translation. The reason for integral or external DACs is to translate the digital (not analog) to analog otherwise you couldn't get anything from the pits. If you mean analog is defined as something physical with a surface that provides information in a digital format. Then OK I guess? but that is not what analog means to virtually everyone else.

One of things that I was refering to is the "analog eye pattern".
Contrary to popular opinion, tranports take analog information from a CD and 'build' a digital signal. Only then is the digital signal sent to the DAC for conversion back to analog.
The sound coming from our speakers is only going be as good as:
1. the transport's ability to pick up the raw analog input signal as a reflection of the laser bouncing off the CD (the 'eye pattern').
2. the transport's ability to use this analog information to create and generate a digital bit stream that is a close approximation of the digital bit stream that existed in the recording studio.