Continuity mistake: Roz and Frasier are in Cafe Nervosa near the start of the show and her sunglasses are on the table. However, in a shot over Frasier's shoulder, they are not there anymore. They reappear in the next shot.
Continuity mistake: In the scene where Daphne is admiring her faux sapphire earrings, she says that it is the 5-year anniversary of her starting her work at Frasier's apartment. She actually started working in the 1st episode - which was in the fall. This episode takes place in the spring.
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 ★