They are connected or should I say they have been in past New Era TK's
With how they are attached it allows he shoulder bell to come open quite a bit as there is no loop of elastic which we see on OTTK's. I don't know if it was for more movement could just have been the way they tackled how to connect them, but it does streamline the look with no external elastic loop like OTTK's.
"In these images we can see Velcro in various places as well as some sort of plastic hook lines connecting the shoulder bells to the biceps."
Great thread here on comparison between the OT and R1 TK's