I think he means mastering as in mixin the SMART system with manually doing things(which in its own right sounds hard to do and incredibly epic...sorta like doin a kickflip at a slow speed down some stairs the first time in skate when ur far to used to the tony hawk games)
I got this idea too, not that it was some system you needed to conquer to play.
I think the real intricacy of the SMART system should be difficult to get just right, but i dont want to have point zero reflexes just to gain benefit. It should be something, that for those who practice it regularly, will quickly notice its benefits, and eventually and intuitively mastering it with out really realizing it. However, those who just stick to the smart button and rely on it more then not, would likely have difficulty when performing maneuvers that require the player to mix and match smart and manual combo's.
And i'm talking about just using it on an intuitive level. Not highly practiced "i go here all the time" routs, but whenever a well practiced player would need to get some where smart couldnt do on its own, they could gracefully find their way up with out much thinking.
This would also make the movement system more realistic to parkour. As one becomes more talented in the trait, the more they do it, the more they practice it and the more techniques they acquire, they will suddenly find themselves not only seeing and finding more paths in their environment they had not noticed before, but they will try these paths intuitively.