You would both have to fail the same move to lose the secret. For example, if you have to hit every dance move perfectly, it is enough that for every dance move, one of you is able to perform it perfectly. Additionally, for any of the secrets which require you to do something “perfectly, ” only one of you has to be perfect and it doesn't have to be the same person each time. With two players, your potential for collecting coins (which is your score) greatly increases because each of you can go after separate coin groups. Most of the tips for attractions are on the attractions page of the walkthrough, but there is one general tip that applies to almost every attraction: Co-op does greatly help completing many of the attractions. It's usually not too hard and the game is often generous about photo locations. In that case, try repositioning yourself and approaching the photo target from a different position or direction. When taking photos, sometimes the game won't recognize that there is a picture to take.
