#955
I've taken a closer look:
Quick spoilers:
I can confirm your observation: stringForKey() returns null, and intForKey() crashes.
1. In fact, I _can't_ reproduce the behaviour you observe with stringForKey(). intForKey() still crashes though.
2. I'm no longer convinced this is even supposed to be a feature—see my writeup in the ticket above.
I'd be interested to hear counter-arguments, but let's continue discussion on GitHub. I'll summarise here later if needed.