I can see where they are comming from but I agree prob not necc?
"NOTE: While the Vanilla is a very well-crafted suspension fork, the plunger shaft and damper rod tend to "spin" when one attempts to remove the bottom fixing nuts. This can be extremely frustrating, as no Allen recesses or screwdriver slots have been provided to assist in holding the shafts still. The first few steps illustrated below can help to solve this problem by compressing the fork. Once the fork has been torn-down and re-assembled, subsequent tear-downs are usually easier. However, you (or a machine shop) may want to cut SHALLOW* screwdriver slots in the bottom of the plunger shaft and damper rod, allowing you to skip this fork compressing procedure in the future. "