I use it with volume leveling.
When I play an whole album file, Adaptive Volume is in (fixed) mode and the volume is right.
When I play my files shuffled, Adaptive Volume goes into (adaptive mode) even though the file it is playing has been analysed.
I've had a chance to test this now. I think it only applies to playback using Play Doctor, and this is likely because the playlist is dynamic.
Normal playback, even with a fixed playlist of random tracks:
VL = All tracks/albums play at the same loudness. For albums, the average of an album is used.
AV = All tracks play as loud as possible.
VL+AV = All tracks/albums are leveled, and the playlist is adjusted to play as loud as it can without affecting leveling.
Play Doctor:
VL = All tracks play at the same loudness. If tracks from the same album are next to each other, the average will be used for both.
AV = All tracks play as loud as possible.
VL+AV = All tracks are set to the same loudness. Adaptive Volume switches to adaptive mode rather than fixed, since the playlist is kept at a fixed size of 100 tracks, and the average level would be changing with every track change.
That said, I wonder if it may still be best to use the average of the current playlist, even if that average is changing with every track. I feel like that may keep volume more level overall.
Generally I would only recommend enabling VL on its own, so long as your amplifier can get loud enough.
You may wish to use VL on its own and add a fixed amount, such as +6dB volume via the Parametric EQ if not.