I really wonder about this ?!?!?!?
How much time do we expect to gain by having one or two CSRs take the bags on board locate the seat and overhead bin
place the bags there (two at a time) and return to the gate lobby to get two more until the mission is done.
This all relying on having willing and co-operative customers tender the carry-on baggage early enough to facilitate this ?
Compounding this if the flight is arriving to clear the aircraft of arriving passengers and any pink checked gate luggage
and working around flight crews changing; catering; cabin service cleaners etc.
A well chorused chaotic mess - "BUT" bravo to the idea to try and speed things up boarding !

Personally Delta would do better to allow 2 FREE checked bags and get the bags out of the cabin to begin with like the
system used to work. The ramp crew with the loading machinery can better handle the volume of bags !
Passengers without baggage board faster with less complications than the present system !

JMHO and YMMV of course