Are you able to click down in steps when you are not in your highest/outermost position on the FD? That is, if you can downshift from position 3 to pos 2 and then to in pos 1 with the single click/short throw feature, then cable tension could be the issue. If you cannot single click down from #3 to #2 then I would think that cable tension will not fix your problem. The cable tension adjustment I believe will only solve an upper or lower limit cable tension shifting problem. If the FD is really out of adjustment and you are only making it to your next to last position it could mask your top position.
Good Luck. Interested to hear if the fix works.