You must purge yourself before finding faults in others. When you see a mistake in somebody else, try to find if you are making the same mistake. This is the way to take judgment and to turn it into improvement.
I also say with backbends, you have to be cautiously bold. Not carelessly bold. You have to descend to the dictation of the spine. You cannot command from the brain to do the poses. As you play with a child, guarding the child from injuries, similarly you have to play in backbends, guarding your spine.
