I believe they refer to the stich on the sleeve placket 7th photo down.
I think the the extra cost on this shirt, due to the hand stitching is a complete waste.
the regular machine stitched shirt is very well made.
the hand stiched embriorded gusset is strictly decorative and serves no purpose.
I guess it is time to post the pictures of the lanvin shsirt. where hand stitiching is discrete and not obvious.