Can you describe the contrasting styles of service being performed by Damu Anna and Mavshibai right before their argument?

Yes, their styles of service were markedly different. Chapter 24 details that Damu Anna, an elderly man with no teeth, was performing a gentle service. He was leaning forward with his hand on the railing, slowly pressing Sai Baba's left hand. In contrast, Mavshibai, a devoted widow, was engaged in an extraordinarily vigorous form of service. She was pressing and churning Baba's stomach with both hands, likened to grinding or churning a pot of buttermilk. Absorbed in her service, she pressed fearlessly, causing Baba's body to move up and down, a strange but loving service that ultimately led to the humorous confrontation.