Continuity mistake: Frasier is in Mr. Safford's study talking to him. As Frasier says "a little unconventional," his right hand goes up to his chin, gesturing. As Safford answers, Frasier's hands are grasped together in front of him, with no time for natural change.
Continuity mistake: Frasier is arguing with Niles in the kitchen and removes a large bottle of water from the fridge. He takes off the cap, and pours water into a glass. Immediately the shot shows the bottle capped again while Frasier and Niles continue talking.
Answer: Nanny G (Nanette Guzman - played by Laurie Metcaf) has been a children's entertainer for twenty years, and tells Frasier, "Do you know what it's like to play the same character for 20 years?!" The joke is that Kelsey Grammer has been playing Frasier Crane since 1984, when the character first appeared on "Cheers", so Kelsey in real life has been doing just that!
Super Grover ★