This is a video using a walking foot - but she is
also sewing the lines in the
same direction - not reversing directions.
http://quiltingdigest.com/6-great-ti...hine-quilting/
Another article- using a dsm - but I would think the same ideas would apply to using a long arm machine - she also suggests starting all lines on one edge to minimize drag.
http://quiltingdigest.com/6-great-ti...hine-quilting/