From a place of total ignorance, why would telegraphing a particular false strategy to your competitor in order to get them to respond in a way that is profitable to you be illegal?
That said, there are narrow instances where you can place less-than-real orders in a market [0]... it just has to be a market that is nearly and completely illiquid.
[0] https://www.bloomberg.com/opinion/articles/2018-12-04/trying...