Other mistake: The guy who plays Clive in this episode has one of the most appalling accents I have heard. He's apparently from Manchester, but sounds like a sort of cockney South African. His accent slips around all the time; it's very poor. I wouldn't normally submit it, but his is so shockingly bad I doubt anyone would be fooled into thinking he was British.
Other mistake: When Frasier enters the apartment, Martin and Sherry are talking in the kitchen. If you listen carefully to what they're saying, their conversation makes no sense. Martin says something along the lines of "Daphne is really a very nice girl" before suddenly, in a very different tone of voice, he says "You're right, we're not getting enough privacy around here". Seems like a big chunk of conversation was edited out.
Plot hole: In this show Daphne's former fiance, Clive, shows up. They had been engaged for several years in England. However, in Series 1, episode 11 (Death Becomes Him), Daphne talks about never having had a serious boyfriend, and goes into some detail about how people tried to set her up with eligible men. As Daphne is open about everything else, there seems to be no logical reason for her to not mention she'd been engaged.
Continuity mistake: In this scene, Martin and Daphne are arguing about Martin buying the gift basket for Daphne because Daphne knitted the sweater for Martin. Daphne says the basket cost too much, so Martin begins to take items from the basket and put them on the table. Then as the argument progresses Martin and Daphne decide to take back their gifts. Martin places the gift basket on his chair (the two items that were taken from the basket are still on the table) and Daphne takes the sweater. A minute later they make up and agree to re-exchange the gifts. Daphne gives Martin his sweater and when Martin reaches for the basket, all items are there, including the ones that were still sitting on the table when he put the basket on the chair.
Continuity mistake: During the opening credits, Bulldog is on the phonein the hall at KACL and he throws a tennis ball at Frasier, who stumbles around trying to catch it. During the scene we see an extra behind Bulldog go into one of the rooms - but we see her do it again just a split second later - and the second time she has a paper under her arm, where she had nothing the first time.
Continuity mistake: When Roz and Frasier are in Bebe's office, and Frasier is exclaiming about her taking digitalis, the water glass in front of her is empty. The rest of the shots show it being about half full, even though she never refilled it, and there was no water source to be seen.
Continuity mistake: At the beginning of the show, when Niles and Frasier are in Cafe Nervosa, the man behind them has a paperback book which is open with all the pages fanned out, and then it is lying flat, then fanned out again, and so on. It is not a case of him changing the book naturally, as the positions of other things in the shots change slightly as well.