Explain how she performed terribly. I’m not saying she did or didn’t, just want to hear your reasoning.
From this chapter alone, I can mention 2 things about Big Mom's terrible perfomance.
1. When Law is on her body and she wants to get rid of him, the way she punches Law is like a puppy irritated with an insect on its body. Looks really childish punch.
2. She cuts Kidd's metal bull, should have known it is useless as Kidd can just reform the bull.
By number 2, I can tell she also won't have clue dealing against Pica golem. Pica has a chance against her.