Personally I don't regard barrier position as that critical in most cases but I think that the important thing is the relative position anyway. Whether the horse drawn 1 starts from 1 or 5 it is still the closest horse to the rail and the one drawn 7 still has 6 other horses between it and the rail regardless of whether it is actually starting from 7 or 12. Except for the Flemington straight (which is a whole different issue) I can't see how offsetting the barriers can advantage or disadvantage any runners over the "correct" positions and therefore can't see how it would affect your form study. You should still treat the horse in 1 as being in 1 as there are no other horses between it and the rail.

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