Monday: Legs, chest and Triceps
Tuesday: Back, delts and biceps
Wednesday: Off
Thursday: Legs, Chest and Triceps
Friday: Back, Delts and biceps
Saturday: Off
Sunday: Off
Mike Mentzer used this split at one time. Chris Dickerson too at one time. Bill Grant used to train four days a week. Not sure how he did his split though. Mike Mentzer started off using whole body routines for three days a week. He won the Mr. America using this. He then went to the split I described above. After this he used a Mr. Florida Frank Calta inspired rotation for recuperation split. It went like this.
Monday: Legs, chest and tricep
Tuesday: Off
Wednesday: Back, Delt and bicep
Thursday: Off
Friday: Legs, Chest and Tricep
Saturday and Sunday off
Next week he did this.
Monday: Back, Delt and bicep
Tuesday: Off
Wednesday: Leg, Chest and triceps
Thursday: Off
Friday Back, Delt and bicep
Saturday and Sunday off
Mike didn't care about the days of the week. If he took an extra day off he just continued where he left off. The workouts he suggested were optimal when he retired is something he never did in his competitive life.