Voigtlander 28mm viewfinder

The ribbed Leica SBOOI has a series of dashes at the top of the finder window. Theses are for pairing the finder with the 1F and are to be used as an aid for close focus. On bodies with a rangefinder, those same lines are too high to be useful. The Voigtlander 28 mm finder has a set of dashed lines at the top. If the finder was marked 25/28 it would make sense but this one is only marked for 28. Any ideas or answers? Thanks.

Parallax correction for up close so you don't cut people's heads off.

That's was my conclusion. Someone over on LUF found a blurb from the B&H website that gives a good description. It's a really nice finder and too bad Cosina stopped making them.