Bryan's goals and mine are a little different, so I come at this from a different perspective. I'm after authentic Real Ale, slightly oxidized and nearly flat.
Here are my two spunding plans:
Plan A
Ferment to spunding point
Purge keg/do nothing for cask
Rack to keg/cask
purge with bottled CO2/roll cask around
spund/secondary fermentation
Push with gas/settle, vent, tap, serve.
Plan B
Ferment out entirely
Purge keg/do nothing for cask
Add primings to keg/cask. Either sugar, or fresh wort if available.
Rack to keg/cask
purge with bottled CO2/roll cask around
spund/secondary fermentation
Push with gas/settle, vent, tap, serve.