The "Why" was mostly addressed under the "Why are you trying this out in the first place? Did the standard Lead Link / Rep Link configuration fail the Circle?" question. However, it is jumbled in the middle with everything else and should be one of the first things you see, so I shall adjust that! To sum it up:
We rarely had any need of our Lead Link anyway. Other than Role assignment (which was always just done at our own request anyway), there was not much that ever needed to be done as a Lead Link, because we quickly and efficiently took care of whatever was needed as a team. Once our Lead Link resigned, we chatted and realized we might be able to do it in a way that is more efficient than having a Lead Link. Thus, it is half experimentation, half self-actualization (in the Hierarchy of Role Needs).
Hopefully that mostly addresses it, but if you still have questions, please do not hesitate to ask!