When Jerry shakes his head at Elaine for pronouncing the tenor's name wrong, he faces her. In the next shot, he is standing at an angle to her and turns to face her.
Elaine comes into the office at the Convalescent Center and stops just outside the door. It then cuts to a close-up and she is in the office.
Just before Estelle walks in on Kramer and Frank's pool game, Kramer knocks the cue ball off the table. It reappears on the table later without anyone putting it there. Other balls also move around between shots, particularly the green-and-white one.
The flight attendant puts Jerry's bag in the overhead compartment, but allows him to hold a very large box on his lap. It too would have to be stored, or else checked.
The orchestra which The Maestro conducts is far too small to produce the full-scale Overture to the Marriage of Figaro which is heard. The orchestra is pretending to play while an actual orchestra is edited in.
Sally (Kathy Griffin) says the BBQ sauce she brought is the pride of Memphis, but the box says it's Bull's-eye BBQ Sauce, a product of Kraft Foods, a company founded in Chicago, IL.
Elaine (Julia Louis-Dreyfus) tries to make out the last name of the third tenor's signature, but the poster the Maestro (Mark Metcalf) opens in the next scene has all three tenors' names displayed.
You can see Estelle, George's mother, outside the door for a few seconds waiting for her cue to enter the billiards room where Kramer, Frank and The Maestro are playing pool.
The Maestro first notices his bent baton as he begins conducting at the Queens Convalescent Center. But He would have noticed it earlier when he left the Costanza's house.
Elaine goes to see one of the Three Tenors singing. She refers to him as "The Other Guy" (aside from Plácido Domingo and Luciano Pavarotti, therefore being Jose Carreras), for she cannot remember his name. She buys a poster for the Maestro to get it signed by "The Other Guy". Once he signs it, she cannot understand the handwriting and keeps calling him funny names. However, when she spills the sauce over the poster, we can clearly see the beginning of the name "Carreras" on top of it. It is very unlikely that she has not read the names on the poster (and equally strange that a poster announcing the concert does not have the names of the tenors).
Deena says that George should be in a sanitarium after seeing him with the doll in Monk's. She most likely meant asylum. A sanitarium is a convalescent hospital for people recovering from physical illness, whereas an asylum is for treatment of mental illness.