His problem IMO is he's never had a footballing brain - a bit like Walcott really, or going further back, our own Darius Vassell. Pretty much guaranteed to choose the wrong option in any particular circumstance: Pass it when he should be shooting, blast it straight at a defender when a simple lay off for a tap in is on, dribble down a blind alley inevitably going nowhere. I might also add that his first touch is pretty dire for a player at his level.
Last season he seemed to have improved because Pep taught him where to go and how to move to get tap-ins, of which he got plenty. And a few pens won by charging into the box and drawing fouls.
But it seems to me he's now back to square one: A great athlete and will always get the odd goal, but 9 times out of 10 (and I mean that literally) he just fucks things up. I am not sure we will ever see a radical change because I am not sure you can coach this. It's a certain je ne sais quoi that the top strikers all have - the vision to see what's the right thing to do in a blink of eye, in a split second. Ras has never had this.