Not just "Leveled up using swords, this gives me a great idea for some spells!" but the Experience point based way of doing skill-based RPGs. Got three levels in New Vegas doing nothing but shoot coyotes? Well now I'm a Scientific genius with a minor in medicine.
I'll take the disconnect between Skyrim's perks and skills any day, at least at some point I had to have leveled that skill enough through usage to be able to put that perk there anyway.