Positions Saved Every Tick play back twice as fast? [1.10.2 although I assume every other version]

[Acrogenous]

So Im making a tas ticksaver for minecraft speedrunning. its meant to "record" the players position every tick and play back at the same speed but for some reason, on timing it, it appears to play back twice as fast?

public void onUpdate(ItemStack p_onUpdate_1_, World world, Entity player, int p_onUpdate_4_, boolean p_onUpdate_5_) {
        i++;
        if(this.startRec)
        {
            loc.add(player.getPosition());
            pitch.add(player.rotationPitch);
            yaw.add(player.rotationYaw);
        }
        if(this.startPlay)
        {
            if(i <= loc.size())
            {
                player.setNoGravity(true);
                System.out.println(i);
                //player.setPositionAndRotation(loc.get(i-1).getX(),loc.get(i-1).getY(),loc.get(i-1).getZ(),yaw.get(i-1),pitch.get(i-1));
                player.moveToBlockPosAndAngles(loc.get(i-1),yaw.get(i-1),pitch.get(i-1));
                player.setPositionAndUpdate(player.posX,player.posY,player.posZ); //this is to make textures load

            }
            else
            {
            this.startPlay = false;
            player.setNoGravity(false);
            }
        }

        super.onUpdate(p_onUpdate_1_, world, player, p_onUpdate_4_, p_onUpdate_5_);
    }

thanks in advanced

Edited August 20, 2017 by Acrogenous