While we’re not fundamentally opposed to the idea, we also can’t think of a way that this could actually work. The spacing on a yagi needs to be pretty consistent, and anyone who has held a signal stick sideways can tell you that it droops – and as you move around it bobs forward and backward. A yagi would need some way to keep the spacing consistent regardless of any movement and that just seems unrealistic. We get asked about this surprisingly often, but just can’t see any way it could be make practical.