My workout split is EOD. The off days helps my mind rest from the "ball to the wall,kill the weights attitude" Its tough to do continuous days in a row. So mentally im way more refreshed.
As far as physical grow...ummmm thats kinda hard to measure but im sure there is. Think about it your sore from the workout on your off day, so you eat high protein and drink plenty of water. Thats gotta be repair/growth IMO.