I would think that a person almost has to do that. Or, at least, I hope a lot of people do that.
I can't think of anything worse than going to a contest, just to see a dozen Showtime 100 Phantoms, 6 Bumblebee Skyraiders, and 18 Red-Tail Mustangs,,,,,and a dozen individual models.
I would rather see that total (48) all be different aircraft, with the same variety in Tanks and Ships.
I guess my thinking would possibly give me an edge when entering,,,,,but, there is another edge on that knife. That is that a lot of people don't know that the famous red diamonds on VMA's Skyhawks were really Dk Green for that cruise, so they might discard if from judging before it even gets looked at, thinking that the color is supposed to match the Red in the popular decal sheet. If you get that far from the well known schemes and details, you could hurt any chance you might have by being "too unique"
(and yes, accuracy is part of judging,,,,,,,it comes into play during the first cut, when they discard the Orange Yamatos and purple USN jets, etc,,,,,,,,,,the wording is something like "the model can't be a totally fanciful scheme",,,,or wording that means the same thing)
Rex
ps, here is one example of what I meant,,,,,,,,,IPMS does NOT consider paint accuracy, but does include these two sentences in the paint section of the judging criteria
"Therefore, color shade should not be used to determine a model's accuracy. Models with unusual colors or color schemes should have appropriate documentation. "
that is the catch-all that lets your Battleship be some generic gray, even if it doesn't match, but, won't let it be a Blue unless you can document it, lol