My understanding is that oleds are a weird beast. Since there’s no backlight, each pixel can be considered a small colored light, if you have a fully black screen, then it’s essentially off and not using any power. However, there are instances where the peak brightness is limited to a small portion of the screen, because blasting the entire thing of full brightness white would pass the power supply capacity…
That said, let me stress this: it’s my understanding. Not a hard fact, I might be wrong or just basing things on old information.
Oh! The “brassic” guy! I don’t have much help to offer, but I didn’t know that term, had to look it up and found the tv show :D so thank you.
A tiny bit of potential help: you mention wanting to use desiccant in the boat. I’m obviously not an expert, but it sounds like a bad idea, as the stuff absorbs water… but maybe you mean in small amounts, so that wouldn’t make a difference.