What the Faulk
You'll know when you go
That exact situation is literally in the rulebook so I don't see how it'd be a mistake. There is nothing about deception in there. Here's the note:
Pereira also agreed that it was a good call.
Note: The intent of the rule is to prevent teams from using simulated substitutions to confuse an opponent, while still permitting a player (or players) to enter and leave without participating in a play in certain situations, such as a change in a coaching decision on fourth down, even though he has approached the huddle and communicated with a teammate. Similarly, if a player who participated in the previous play leaves the playing field by mistake, and returns to the playing field prior to the snap, he is not required to reach the inside of the field numerals, provided that the defense has the opportunity to match up with him. However, a substitute (i.e., someone who did not participate in the previous play) is required to reach the inside of the field numerals.
Pereira also agreed that it was a good call.