Follow path & Taper animation don't sync

I’m trying to make an arrow moving along a path, but leaving a trailing tail behind as well. You can see how I’m trying to do it in this .blend file:

…and you will notice that there’s no apparent reason why the trail and the arrow are not in sync. Their beggining and ending spots are the same, the duration of their animation is the same, both use linear IPOs (both the curve path speed and the taper key).

I hope someone can tell me what’s wrong, how can I fix it, or if there is another way to achieve a similar effect.
Thanks people :slight_smile:

Sorry man I have been looking on this for a good 30 minutes and I am as clueless as you are.
Good luck though and hope somebody knows the answer.