That does explain it a bit, but I still don't understand why you skip the deep sleep when taking a nap. Does it have something to do with the amount of light shining through when taking a nap? Or is it because of the mindset you have when 'only' taking a nap?

Just a sudden curiosity, but could one manage to go directly to REM when leaving a light on when going for a full night sleep? Or fool your subconscious by pretending you're only going to take a nap?

Thanks for your reply!