So in SW FFG and games like D&D they have s list of incidental actions and actual full actions.
I see an example of making an attacking says with a readied weapon. I would assume drawing a weapon would be an action other IAJITSU would be sort of lame waste of opportunity used. Iajitsu says you can draw and attack in one action and unlocks opportunity such as draw a other weapon or sheathe a readied weapon.
If anyone could draw a weapon and attack pretty much half of iajitsu ia pointless to even have or have written up.