I'll see if I can find you a picture of the crazy solutions the Army came up with in Iraq for protecting TC's. We had some odd looking devices strapped to the turrets so you could be unbuttoned and safe from sniper fire.
Look at this.
I lose tank commanders like you wouldn't believe. I've been sending out "name-tape defilade" instructions to my subordinates but the boots on the ground have been ignoring my orders.
I've played some pretty faithful recreations of the battle in some fairly realistic first person shooters such as Darkest Hour. They're brutal. It's all smoke and chaos with bodies piling up until someone gets lucky enough to break a defense. Then it's a mad dash to find the next wall of defenders who make you pay for the ground.
I had something similar happen when I had a jeep parked where one of my riflemen wanted to line up. Instead of moving nearby, he began sprinting across the map. It was weird.
If you have the ammo, Wreck gives some good advice. Advance through the trees behind a wall of lead. If you can support from stationary units, even inaccurately, all the better.
Also, just because you have an ATG crew flanked and under fire, don't expect that they will fall easily. ATG crews are incredibly resilient and hard to destroy.