14-Day Split.. Opinions:?

I am curious about a 14-day split. I am seriously thinking about starting up wtih a 14-day split. Training each bodypart twice a month.. to many of you I am sure that youre quicky going to comment on undertraining. But here is my current split.
Day1-legs, lower back
Day2-chest, calves
Day3-back, shoulders
Day4-arms, forearms

And I am spreading this out over 7 days. I have been getting SO extremely sore that I cannot properly perform in each workout. I dont know why or how.. I am seriously thinking about switching over to a 14-day split. I need some serious opinions guys.

Sun- legs, lower back
Mon
Tue
Wed- chest, calves
Thu
Fri
Sat

Sun- back, delts
Mon
Tue
Wed- arms, forearms
Thu
Fri
Sat

I am following NHE by Rob Faigin so I am eating low-carb at all times with a huge carb-meal twice a week (postworkout). Please lemme know what you guys think..

:cool::cool:

I am training pretty low-volume too 4-6 sets per bodypart.