It's been a little while since I reviewed the rules, but that code 0 could also trickle it's way to F18 as I don't believe the rules stipulate anything about spinnakers other than the area measurement.
It is an intriguing question.
I could have used the code zero during a recent distance race (Milt Ingraham 'round Anacapa Island). Winds were less than 3-5 kts for the first 4 hours, upwind leg. Got thrashed pretty soundly by one of the two I20's by the upwind mark. We were more than 1.5 miles back when we put up our chute. Wind came up just a little and amazingly we were able to reel in the leader and passed him with less than a mile to go.
Not sure the code zero would have been able to catch up like that...but if we'd had it on the upwind leg, we might not have needed to.
