Yes What happens is that blocks dropping from above a cleared line counteract the parity problem created by the odd number of T's. 5 blocks (an odd number) sw

Yes What happens is that blocks dropping from above a cleared line counteract the parity problem created by the odd number of T's. 5 blocks (an odd number) switch parity by moving one position orthogonally. More generally, any odd number of line clears will reverse the parity of all remaining blocks above, which can be an odd number.