I have seen some quilters add the batting as the progress in the quilting. This is different than a quilt as you go , inthat the top is completed in the traditional manner. So if you are working from left to right on the quilt , the rolled up part under "the arm" is thinner becauase the batting has not been added to the backing and top. I Have tried this on smaller projects just to see if I could mange the technique , and I have to say they are on to something. I found adding a few feet of batting as the quilting progesses to be much more favorable than trying to STUFF and manage that whole quilt.
I use warm and natural batting so adding the batting via a long zig zag stich is really easy. I cover the area previously quilted , and do use spray as I am adding to the batting.
It far from the capabilites of a long arm , but it gets me further than the "stuffing" , rolling , and frustration techiniques of working with the whole quilts top , batting and backing.
It is still my preference to send out a full or larger top,as they ( long arm pros) can get better stitch regulation , and do more curves ( easily) than I can manage with only about 6 inches from needle to machine. But for straight lines , stitch in the ditch, or just a gentle curve this is not a bad option.