Snag:
Two ways to line up the cresting stripes and the splice. make the feather longer than needed, splice then cut too length measuring from the splice too both ends. Or do the splice after the arrow is fletched. It can be done the way you did it, however every measurement needs to be very precise. Its extremely important that each crest be exactly the same size and in the same location on each shaft.
My mentor use to say a true arrowsmith will not be able to tell any difference in any arrow in the dozen. Its easy to make one that looks good, not so easy to make 12 that all look the same when laid side by side.
Bob