Seriously, the second I saw him grabbing a sword I was thinking in my head wtf is his plan cause thats fucking retarded, he not trained with a sword and Ras is a master.
In all the episodes I've seen, Arrow uses Eskrima/Arnis (Fillipino stick fighting) the most, he also uses Wing Chun dummy for most of his open hand to hand combat training. As lame as this will sound, I've studied JKD, Arnis, and Wing Chun for a few years, by no means an expert -- and they all flow very naturally together. The complexities of footwork from JKD, the Trapping and upper body movement from Wing Chun (which is JKD's roots) and the footwork and striking patterns from Arnis make for a formidable groundwork for a fighting system. Throw in a little BJJ and you've got yourself the Arrow.
While Arnis starts with Rattan stick/s, it directly translates to bladed weapons as well, as long knives are very commonly used. It then transitions to open hand fighting. An Arnis practitioner is just a dangerous without a stick as with a stick.
This is the reason why Oliver chose the shorter of the swords available and most importantly "paired" swords. Butterfly swords (which these are not) are very commonly used in Eskrima because the style focuses on attacking the hands of the opponent and Butterfly swords are short, wide bladed for parrying and have very heavy guards to protect the hands.
There's no debate that it appeared that Oliver phoned in that fight, he seemed totally unlike his normal economic, thoughtful and precise self. I believe this was deliberate on behalf of the directors (and I think poorly thought out) to club home the message that Oliver is *vastly* out skilled by Ra's.
But... saying that Oliver is terrible with swords is just wrong.