marky_mark:
Would I need to re-enable the clock before enabling the watchdog timer/calling sleep; or would that in itself do it?
I'm not sure if we are talking about the same thing here.
Before calling sleep you want to shut down as much as you can. Afterwards you turn things (like the servos/timers) back on. Calling sleep itself will shut down quite a bit. The various sleep modes are relevant as to what exactly gets shut down.