Creates a right shift just like a low pH would

So 2,3 BPG is an intermidiate in gycoysis with two phosphate groups (note its negative and when we exercise alot will be produced). So it can only bond to a hemegloban without any of the four oxygen, it connects to two postive groups (remeber 2,3 BPG is negative) and causes a comfirmational change that (will bound) causes HG to be useless.