I will say this. If you are making good gains with your routine, then stick with it. Forget what others say. Everyone thinks they are an expert. Many are just skinny guys behind a computer screen who think they look good in their tight Aeropostale' shirt, with a fauxhawk. Screw them.
Many people gain well on working a muscle group hard, once a week. I do this right now:
Day 1 chest, triceps
Day 2 legs
Day 3 back, biceps
Day 4 shoulders
Thats it. It gives me plenty of time to rest, eat, and grow before my next exercise session. Get some ideas, study, but form your own opinions based off of your own experiences. Yes, the split you named is a little outdated, but I still remember people being buffed in the 70's and 80's who used those routines.
Find out what's good for you. Good luck.