It's based off the claim that your proficiency in a given skill has no impact on your ability to use that skill. What I've read is the higher your skill level the more perks in that skill will be available to you to unlock when leveling up, but if you don't take any of those perks then it is the same as if your skill level were zero. In other words, there is no difference in damage dealt with a sword between a character with 10 points in One-Handed/no perks and a character with 100 points in One-Handed/no perks.
Pete Hines confirmed, that's not true. Give me a moment to find his tweet.
EDIT: It's 8 Nov tweet, I'm not sure how to link exactly to it, I'm just quoting.
@ScottLufkin No, your level in a skill still matters. The Perks tend to enhance what your skill does (eg, how much damage with 1H weaps)
@DCDeacon @ScottLufkin So leveling up in 1handed WILL increase damage done without taking perks?
@FuktLogik @scottlufkin yes
I suppose this makes debate pointless
