If you can do it and stay within the safe temps and voltage zones and you have it stable then... yea it is worth the time. Every little bit helps and plus OC'ing is fun
You won't see major improvements 100mhz at a time though. But I would guess your score of 3839 might jump to 3900. Maybe less of a jump. I am not sure. I know with 3dmark06 even the smallest increase made the score jump quite a bit because it was so cpu biased. Since 3dmark11 is still a synthetic benchmark I would imagine it would still be noticeable in the score.