If this is a standard feature, maybe it shouldn't be hidden under /debugoptions?
If this is good for a single seat only, why does the setting read "Multi seat setup: use UNC paths"
Keep in mine that UNC is used in singleseat (if i'm not wrong)
I think what Seb meant was that in single-seat mode, the timeshift files are always read/played directly (as they are normally on the local machine). This is exactly like the multi-seat 'UNC paths' situation, except that it's using 'local' file paths e.g. C:\ProgramData\..... instead of \\<remotePC>\..... etc.
By default, multi-seat uses RTSP where the server 'push' streams the data over the network to the client (rather than the client reading a remote file, as happens with 'UNC paths')
'UNC paths' has always been a 'debug' option because it has problems on some systems - we've made considerable improvements to it in MP 1.8, so maybe we should make it a normal, visible, option in 1.9 (to be decided).