The best I can find is a Bitbucket thread discussing it, among others. It was part of some talk in 2021 about getting the Diffiemorphic DAZ-Blender importer to align with the 'moving target' of the latest DAZ/Blender combo (yawn...).

This control appears to be 8.1 specific and (quote).... "can ON / OFF some eye-look morphs, with eye rotation" and it has "no Controller". My guess is then it may be needed for face morphs that need to be able to control eye-look, so as to keep the eyes visible in the sockets? That's just my guess.

I'm also guessing that you're asking because you want a 'look at the camera' function that can be animated. In which case you should look at free script mcjStareAtTheCam (2020), which works across all Genesis to 8.1 and (apparently) most animal figures. You select the Head and the character will then look at the current camera. The script can have the eyes keep looking at the camera across a set range of animation frames, if required.

---

Learn the Secrets of Poser 11 and Line-art Filters.