Colombo - Murder under glass

Not one of my favs, for sure, but ok. There's Colombo speaking Italian... and not bad! The characters were nothing special, the murderer was arrogant and very annoying when he played charming (charming? really? :/ ) , but the plot was not bad at all.
Paul Gerard is a food critic, and three restaurants pay him to talk well about them. One of them, Vittorio Rossi, has had enough of all this, thinks he doesn't need him anymore and wants to stop paying (we're talking thousands of dollars), not only that, he threatens to expose him, right to his face... Gerard goes to have dinner with Vittorio at his restaurant, then leaves before tasting the wine, going to pick up an important Japanese man at the airport. When he's already gone, Vittorio opens the bottle of wine, drinks some and dies.
The young waiter just came from Italy and doesn't speak English, but we're told that he phoned his family in Sicilia, and the Italian Police called the American Police, and voilà, Colombo shows up.
Gerard returns to the restaurant after being called by the police and talks to Colombo, saying that he feels fine, and the investigation starts.
It takes Colombo quite a while to realise how the wine had been poisoned, which is the strangest thing of the episode, because it seemed rather obvious to me, the only possible way. Once the food has been discarded and he knows the poison was in the wine, then there's only one way possible. I mean, the waiter picked a random bottle among many in Vittorio's restaurant, nobody else touched it, and the only thing that came in contact with the bottle was the opener.
Anyway, the episode starts with Gerard's own tv-show where he speaks about food, and he explains how to cook fugu, so it's no surprise to the viewer that he used the poison of this fish to kill Vittorio.
Not having a clue, the police can't find out what poison it was, but Colombo is very persistent to say the least, and even shows up uninvited at Gerard's house while he's having dinner with the Japanese man and they're about to eat fugu, a rare specialty, and obviously the man explains to Colombo about the poison, thinking that he's sharing a curiosity while at the same time complimenting Gerard on his ability since not everyone can cook that fish.
At the end, Colombo calls Gerard to Vittorio's restaurant to cook together, he's making scaloppine, while they talk. Gerard knows that Colombo is getting too close to the truth and most importantly that he won't stop, so he goes again with the same trick he used before: switching the bottle opener with the one poisoned that he brought from home. Colombo drinks his wine after his attentive look, but then explains to him that he marked the opener and now the opener on the table has no mark, so he knows that he had tried to poison him and therefore he switched the glasses, and now he takes the other glass as proof - ... it's all very nice and all, but shouldn't all the wine in the bottle be poisoned? If it was poisoned with the opener, all the bottle should be poisoned, not just one glass, so switching the glasses wouldn't be enough, would it? ... I mean, while watching it one tends to just go phew our Colombo is ok and clever as always, but then if you think about it, it's absurd and very wrong, there's no way you can poison one glass and not the other if you put the poison in the opener you use to open the bottle....
Anyway, Colombo sits again and tells him to taste his scaloppine and tell him what he thinks of it, and Gerard says that he really wished he had chosen to become a chef....
A funny thing was that all Vittorio's friends were showering Columbo with free food :-p
Gerard was so full of himself, he had to ask Columbo when did he start suspecting him, and was very much taken aback when Colombo told him that he suspected him from the very beginning, as soon as he saw him. Well, he's right, you know, if you got called and got told that the man you just dined with had died of poisoning, would you be so calm ? Wouldn't you be worried about yourself, maybe go to a hospital? Gerard (who clearly had no intention of stopping there for the whole dinner since he had planned to go to the airport), went straight back to the restaurant when the police called him, totally fine and very calm, not in the slightest worried that he might have been poisoned too...

ITA vino d'annata