I don't write the rules, I'm just telling you what they are. I guess it boils down to the idea that bluffing is banned in financial markets. What differentiates making a bluff from a regular raise in poker? You have to 'make good' on the bet either way, yes? The difference is that you're 'hoping' that you don't get called, 'hoping' that your opponent folds. Not allowed in markets. Probably a good thing too, or they'd be even more chaotic as they degenerate into bluff and double-bluff. Having said that spoofing is still widespread, likely because it is hard to prove and some regulators aren't as tough on it as they should be.