My suspicion is that nobody could tell the difference between sub milliseconds, and several or even tens of milliseconds so long as the latency in both channels is the same. The stereo imaging isn't going 5to change if the L/R signal transient is at 0.000/0.0001ms, compared to 3.000/3.0001ms. The phase difference is the same.
(Surely that church organ delay is an artefact of the pneumatics, not the speed of sound travel time between the player and the various pipes?)
that Church organ delay is very much an artefact of the speed of sound travel time: the pipes sound half the cathedral away from the organist. In some churches this is made even worse because there is a conduit across the top of the vaulted space injecting sound into the other end directly, so then you get both a direct wave and a diminished one with a massive delay.
Super confusing, the best way to deal with it is to just put on headphones and only listen to the direct sound.
(Surely that church organ delay is an artefact of the pneumatics, not the speed of sound travel time between the player and the various pipes?)