your probably right, it was a little dodgey, but everyone knows (aside from the Dodgy jump from the deck/ one handed pred/ and alien pig Squeel!) That was probably the best scene in the movie, Thing is the fight did'nt need to be that long, a shortned down, darker lit fight and it would have been perfect.
I liked the tail swing, and once the predator throws the alien and gives out the scream, its like "game on!" plus you had probably the Single best shot in the movie, the Alien on top of Celtic screaming......