Namelessone25 added a post in a topic
Not quite true, for example
Where you look: 1 2 3 4 5
Where he is : 2 1 2 1 2
You'll notice that since he is able to move before you get to look in another hole, if the groundhog just switches back and forth between 2 and 1 you wont find him using a sweep.
I noticed in my previous post's picture, the "333" part was redundant, so I've just changed it to a single 3.
So here is my final answer: