I suspect this question arises out of a discussion on another forum where I use another name so I should perhaps declare an interest.
The normal foot position on step 3 of an open telemark is side and slightly fwd. That would be used for most, if not all, follows including the weave from PP, quick or otherwise.
The different position of side and slightly back is used before a wing to allow room for the man to turn and the lady to move in front of him making half a turn in the wing. This is using the standard technique alignment, moving from DW to DC (as man).
If the alignment used was different, and less turn is made, then the normal foot position could be used. Compare the wing following an open impetus which has no turn for the man as standardised.