Ha, as long as they sell aluminum arrows there will be some need for 4" vanes.
Ha, might experiment with some 4" vanes I have and cut them down to 2" vanes with a sissors cutting from top to bottom and use them on some yet to buy carbon arrows. Cutting three vanes will be worth it to use on one carbon arrow. Well I have to stock enough for the remaining aluminum, though. In case the 4" vanes get discontinued first.
They ended the career of the TC Hawken, so I can't trust the arrow people. I have little faith. Change is always in the air.
I can experiment. I don't compete in 3D events.