Is this a 21 Personnel Twins Formation, or a Single Wing Formation? Offensive Coordinators are bad people... It’s back to normal on this episode of the JDFB Quick Clinic, for a look at defending a 21 Personnel… or maybe an unbalanced Single Wing formation… with the 4-2-5 Defense. When you’re looking for ideas on how to shut down a weird offensive set, there’s no black and white answer. OK, there’s no black and white on defending anything. But these weird ones… yeah, the question is unbalanced? Is it Single Wing? Is it both? Check it out, we’ll decide. This JDFB Quick Clinic question was sent in on Twitter. You can send in your questions for the JDFB Quick Clinic by messaging me on Twitter @footballinfo or sending an email to me at joe@joedanielfootball.com.