This model changed a lot over the past 100 years. At the beginning, there was maybe only the 91 mm version available. The Nr. 207 of the 1903 catalog shows this knife, but with a standard reamer, not a nailfile on the back. In 1942, there was also a 84 mm version available, named 207 k (k = klein (small)), with a long nailfile on the back. Later, they dropped the production of the 91 mm version what I`ve heard and only the 84 mm golfer was produced. Now, they changed the production from 84 mm to the 91 mm compact. Now the nailfile on the back on the multipurpose hook looks almost like the very old version of the knife on the pictures above.
I don`t know the reason why they changed this knife that many times, the size but also the tools, leading back to the version of the early beginning. There must be always a good reason to change a knife, because that means a huge adaptation for the production. Maybe the last change was because of the scissors. When the 58 mm knives becoming popular, there was no need for small scissors on the 84 mm knives...