Continuity mistake: Kenny enters the booth, and Dr. Nora's purse is on the edge of the desk. Immediately in the next shot it's gone. Then it's back. When Kenny leaves it's gone again. (00:10:25)
Continuity mistake: Near the end of the show, Niles and Frasier are shaping hamburger patties in the kitchen. Niles has a blue bottle of water which sits on the stove top in front of him. In one shot it suddenly appears on the counter to his right; even though Niles hadn't moved it. By the end of the scene it is back in front of him on the stove top.
Continuity mistake: Near the start of the show, Roz arrives at Frasier's with baby Alice. She is standing near the balcony door in her black gown when suddenly a white spit-up cloth appears on her shoulder that had not been there previously in the scene.
Continuity mistake: When Frasier and Niles are in the restaurant, Niles is under the influence of medication. He lays his head down on his arm just as one of the geniuses arrives and greets them. In the next shot, his head is lying right on the table, with no time for him to have switched positions.
Answer: It equals the record of James Arness of "Gunsmoke" for the actor who's played the same part on TV NOT in a soap opera. If you include soaps there are two main contenders - William Roache, who's been playing Ken Barlow in "Coronation Street" in the UK since 1960. Don Hastings has been playing Robert Hughes in US soap "As the World Turns" since 1960 as well.