Hi all,
We are discussing the added value of explicitly SYNCing multiuser scenes HERE:
http://web3d.org/pipermail/x3d-public_web3d.org/2021-December/016331.html
I am feeling free to add a picture here, to explain what we are talking about:

A) Standalone scene
B) VR multiuser scene, explicitly SYNC’d
C1) MR multiuser scene, explicitly SYNC’d (derived from B)
C2) MR multiuser scene, implicitly SYNC’d (via reality)
All the best
Christoph