I have noticed that anybody who has mastered a particular skill usually has varying degrees of proficiency with sub-sets of skills within the larger skill set.
To be efficient at something does not require you to be the best at all aspects of that skill set.
This is true for the masters as well. While he definitely has a grasp of all the skill sets that comprise his craft, there are many that he focuses on only rarely, and perhaps isn't even proficient in. This is fine because he is remarkably proficient in other areas of the craft, and in some areas are good at but not the best. Just using those skills as supportive elements.
In terms of ratios, it seems to be something like this (for those who have mastered a craft).
He has one skill dialed all the way up to eleven. This is the one aspect of the craft he just excels at, beyond the limits of proficiency. It is almost magical how good he is at it.
Then he has two or three skills dialed up to around 8-10. These skills tend to support the skill that he has dialed to eleven. They make this man a well rounded practitioner in his craft and a master at what he does.
After that, there are a number of skills that sit squarely around 5-7. A lot of them are at 5. They are important and foundational but not the focus of this particular masters expression of his craft. He wouldn't be a master without at least a steady grasp of these skills, but they aren't the most important factors in his success.
Then there are skills he only has dialed between 3-4. These are skills that aren't very relevant to his approach but he can still toy around with from time to time if he needs some diverse tools for a unique situation.
Lastly there are one or two skills that are developed only to about 1 or 2. These are skills that he doesn't find very relevant to his style or approach. He can get away with slacking on these because the rest of his skill set is so well-rounded and developed, and he has created success for himself self without having developed these skills much. That said, he is still aware of their relevance to the craft.
What particular skill sets within the craft are dialed to whatever level is what ends up really defining the master's style and approach, as well as his success.
Now, there is always the exception of the virtuoso, he has way more skills dialed up to the higher end of the spectrum. But one does not have to be a virtuoso to master a craft and find success in the field.
So where am I going with this? When you see some "schlub" or "wimp" out with a hottie there are a lot of factors as to why they are together. Sure he may not be some master pick up artist (though he very well could be. How could you know?) but he most likely has some character traits that are dialed up in a manner that has contributed to this particular success.
Yes fundamentals matter, but there are many aspects to the craft and no one fundamental is necessarily more or less important than the next. However, when certain character traits are strong enough, one can also get away with not being the most proficient in some areas. So you can't really judge someone's success by one area all alone. You have to understand there are many factors that lead them to their position.
Also, from the outside we have no way of knowing exactly what dynamics are set up in their relationship. Or what motivated the girl to be with that guy. There are tons of factors that go into it. The culture they are both steeped in, play a factor. As well as the nuances of their personal psychological make and how they relate to each other.
Too many guys look at appearances (not just appearances in terms of looks, but also how behavior appears from the outside looking in), missing the fact that attraction is a current that runs far deeper than what appears on the surface.