I guess my actual question was can you miss a hanger on a fixture or must you have a support on every fixture?
I would not skip a support, as John mentioned you need to come up with a way to get a support where you need it.
In my picture above out of over 600 supports only a few actually land on a truss. If you notice the fixtures are diagnal...a major pain in the rear.
Anyway we used these from Caddy...
To install most of them you use this tool...
But before we got started I sent an RFI to the engineer asking if this method of supporting from the deck was OK. He approved it and away we went.
I can tell you these are very strong.
BTW, also the fixtures in the above photos are joined with factory couplers with 4 tek screws added per coupling to ensure the fixture could not pull apart and drop.