[ZkinandBonez said:]
Then again he did manage to stand his ground against Kylo Ren in a lightsaber duel so clearly he’s not without combat skills.That was also one of the dumbest parts of the whole movie. Doesn’t work to use one terrible flaw to justify another terrible flaw.
Well, another Stormtrooper stood his ground against Finn with a lightsaber as well. Clearly these guys have some fencing/sparring training. He also shouted “traitor!” at him so he might have been someone who knew him. And if he knew him then they might have been in the same squadron (or whatever it’s called). That scene, despite clearly being an actions scene made for the sake of action, could have been a way to hint at why Finn managed to use the lightsaber so well.