It might depend on the person. I used to be an avid unicyclist, including commuting to work on one every day, and my groin always ached from it. Adjusting, sitting up, etc, never really helped much. It's the main reason I don't really ride any real distance anymore.

I did find that barends helped however, push on them with your hands and you can get some relief. The unicycle in the article has them.