Hi Yukionna,
The limit we put on registration is only to adhere to Leave No Trace, which recommends people limit their hiking parties to 10 or fewer. That being said, many more than 10 people hike the trails in the WMNF every day, so I’d say join your friends and don’t worry about the registration. If you can separate the group into two teams, that would be great. In short, just join the group!
Thanks,
Chris