On the crowfoot, it's negliagble. The ones I have are 25mm from drive centre to stud/nut centre so that's 2.5%. Thats within the tolerance of 5% that Ducati specify, so I'd set the wrench exactly and tighten it up as normal.
the spanner I used to use, with the socket welded in the centre was about 100mm centre to centre so that was a different story