lololol~ that's a great tactic!! Probably quite difficult for a shyer kind of person to pull off though. I'd like to know how an INFJ would treat a crush in comparison to a friend. From what I've noticed, they tend to be quite intimate with their friends as it is. You may have just broken through the distant Fe shield and into the Ni or something crazy like that.
And I just confirmed this in that "how to seduce as an INFJ" thread. They actually do do this. When they want you, they will supposedly make it slightly more clear: more smiles, more focused attention, and that's about it .