Amazing videos Paula, you hooked me to this series now! ^_^ I've watched them until 2am last night, and still haven't finished yet... great stuff!
I can see how the non-combat stuff relates to Nifflas' games, but not sure about the first one, which talks about how difficulty is not so much about difficult execution, but about more choices to tackle a problem (depth). Now, I haven't played all of Nifflas' games, but the ones I have, those had only one way of tackling a given obstacle. Any difficult moment I had was either due to hard platforming, or hard puzzles (ie. execution).
On the somewhat-related subject of Nifflas and non-violent games: I wonder what everyone thinks about Knytt Stories and violence. Is a defenseless non-combative main character enough to call a game non-violent when her world is full of creatures whose sole purpose seems to be to kill her? In one adventure, Juni can be skewered, shot, incinerated, electrocuted or mauled to death, and then I didn't even mention the numerous objects that can crush her or slice her to pieces. Just some thoughts...
Now I gonna go back and watch the rest of the series. Thanks, Paula! ^_^