I once asked them about the trailaire. Their response was that they tested it and found no benefit to adding the trailaire pinbox to the setup. I then followed up and asked about the tri-glide and their response was that they had not tested that version. I didn't purchase either and went with their recommendation.
I think they are saying there is no benefit to the MorRyde if you are using the Andersen so they recommend a block out kit to disable the MorRyde so that the Andersen can do its thing (what that thing actually is will lead to a really long debate here on the forum).
I like my Andersen 5th wheel ultimate companion.