I work with very fine threads, so there's lots of counting when tying fringe. Recently, I tried using the denting of the reed as a counting device twining one round across the warp as a counter. For example, with a 36epi warp just before starting the cloth, I twined junk yarn around the threads in batches of 3 dents, 9 threads per fringe. When off the loom, untwine each group as it is tied. If you have extra harnesses in your design, it should also work to add a shed with 1 fringe group up and one down and be significantly faster to, since you can just weave a couple of shots instead of twining.
This post is cross posted between The Efficient Weaver and Scarf Borders & Finishes, since it may be of interest to each.