I've been working on incorporating more lag in my swing. It's working but my left wrist feels really sore- especially in the region towards my left pinky where the wrist hinges. Is this normal? I also noticed that my left hand is sometimes bowed at impact now because of the lag.
I think to many people focus on lag...I see all kinds of posts here about getting more lag. Lag does create a powerful swing, but if you just have a good fundamental swing lag is something you shouldn't even be thinking about when swinging, it should just happen.
I agree, I think forcing a new wrinkle into your game is going to cause you problems. every decent golf swing has some lag in it, by working on making the proper swing lag will come naturally.
If you're hitting off mats, the pain may be caused by the constant pounding off that concrete base underneath. The location of your pain sounds like an impact injury to me. However, if this is happening just from hitting tee shots, then look to gripping the club too tightly as a cause.
Ease off on the repetitions, lighten your grip, and try hitting off real dirt and grass.