Okay, condescension aside. From your point of view, what was happening when a newbie Stormtrooper with nothing but a lightsaber loss under his belt started landing hits, with a lightsaber on Kylo Ren, a well trained Force Sensitive saber-master? Did you think it was bad writing? Did you think Finn was just lucky? How did you process that?
Kylo was visibly injured, and from what I could tell, toying with Finn in the early stage of the fight. Kylo underestimated him, got bit, and then quickly dispatched him as he should have from the outset.
For me, once three thin coincidences pop up in a film, knowing that the movie has been made with care, I don't look at them as coincidences, but as part of the story.
Here's the thing though, I don't interpret those things the same way that you do. Let's back track for a minute, as I'd like to ask what it is about him that gave you the impression that he was a quick, intuitive learner. The only thing I noticed that he picked up quickly was aiming gun turrets. That doesn't strike me as being too much of a far cry from his marksmanship expertise with small arms. Otherwise, he can't understand droids or wookies, can't pilot a ship, and even struggled to identify (several consecutive times) the spare part that Rey was asking for. Then there was, of course, his "we'll use the Force!" moment as well. I realize that these last two examples were played for laughs, but they still informed on his character. Again, I'm asking in earnest because perhaps I missed something.
As for him bonding with Rey, that one is completely lost on me, as I really don't see the correlation here. He bonded with Poe just as quickly, and there's nothing about their connection with one another that alludes to the Force. Were that the case, I'd imagine he'd have had an easier time locating her on Starkiller, rather than by needing to have it pointed out to him by Han.
Now certainly Han and Greivous' use of Lightsabers as blowtorches and sawblades is notable, but none of them started sword fighting like a Jedi does, which is what Finn did, which is a really hard thing to take as coincidence. By itself could possibly be something new in the Star Wars canon, but with all the otherwise unrelated thin correlations that only have one common denominator - force sensitivity - I don't choose to hold out for more information about what all these things associated with force sensitivity might really mean. Why would you?
As I said before, coupled with the fact that I don't interpret the other correlations as correlations in the first place, I don't see simply picking up a lightsaber and swinging it as a sign that one is a Jedi. From my point of view, the movie seems to want to make that point for us, especially with Finn being a red herring for Rey.
Next question: Do you perceive Finn as slower and less Precognitive than Luke in Episodes 4 or 5? Why is that? When I look at these scenes, Finn seems to move significantly faster, and fares much better in his battle. Is your perception different?
I fully realize how this answer will sound, but I'm gonna say it anyway - I honestly chalk that up to choreography and the era in which the movies were filmed. Even so, if was made very clear that Luke was a Force user, something that the movies have always went out of their way to point out, as a matter of fact.