what happens when you call .play :
set group, server
children loadDefFileToBundle(bundle,server) asSynthDef
create a PatchOut object isPrivate: a public bus is one of the main audio outputs of your soundcard. a private bus is one that will be patched and mixed further down the line. When makePatchOut is called on the top player (the one that actually was sent .play) it plays to a public (main audio output), and any internal children are told to allocate and play onto a private bus.
"resources" include
groups - some players create groups into which they spawn events or groups where they run effects (that must be kept in processing order after the player's primary synth) busses - some players maintain busses for internal use
each of the children prepares into the bundle (and they prepare their children)
samples, buffers needed for efx, sequencing etc.
each child: spawnToBundle
called after the player has spawned on the server