Originally Posted by OptimumRC

I don't know why you would want to CA your diff rings in place?

An additional function they provide is a 'safe' place for the diff to 'give' before slipping the diff balls. An example of this would be when losi went away from D-rings in their XXX platform and have continued the trend of all the other good diff makers like AE to use non-keyed diff rings. I could see how this would be different though for on-road.