Hi maniacbug -
maniacbug:
... I suppose this could be stated more broadly. The available libs do not reset the chip registers to the factory state on startup. If you want the factory state, you have to power cycle. Not sure this is "incorrect".
... - as we are doing this for a hobby, it's probably ok. Just need to remember that only a power cycle gets your device in a properly defined state.
On the other hand, from a design point of view, any lib (for any device, not just the nRF24L01+) which only works if the device is in a certain state on start-up will fail under some circumstances.
Clearly something you want to avoid if that device is mission-critical ... 
A lib which does not a full initialization will probably also fail in an application featuring a watchdog function - as this won't "reset" external chips properly when a restart is occuring. So it maybe a good idea to mention this fact for other users of a lib.
My code of the 2.4 GHz scanner above does of course violate this as well - it does assume that the nRF24L01+ is in the factory reset state when it starts. For a hobby project, I think this is ok. You just need to be aware that a simple reset won't get the nRF24L01+ back into a working state for other libraries/programs... 
Best, cpixip.