Oh! Calcutta
I have absolutely no scientific or empirical evidence to back up what I am about to say, (which is why I am posting it on a blog), but it occurs to me that most gushing raves about Calcutta have a couple of things in common: a) they are written by people who have lived in Calcutta but are not Bengali and b) who have since moved out of Calcutta. Prime examples, other than Mr. Sanghvi, are Jug Suraiya and Bachi Karkaria.
Here's my theory - even though theorizing without data is a capital mistake according to Mr. Holmes: Non-bongs, or Hon-bongs, who have moved out of Calcutta feel slightly guilty of having done so, almost as if expecting Bengalis to accusingly say, "See, I told you they would not stay! They didn't really love the city." So, in order to prove themselves holier than the Pope, more Bengali than the Bengali, they periodically come up with a nostalgic, slightly romanticized account of how great the city is and what fun they had when they were there, before they succumbed to the lure of fame and fortune in points west. Thus, they feel compelled to wear, their fondness for all things Calcutta on their sleeves (the "even though I left, I still love you" move). Not only must they be fond of Calcutta, they must be seen to be fond of Calcutta.
The Bengali on other hand couldn't care less. To him, (or her), Calcutta is the greatest place on God's good earth, he knows it and doesn't give a flying fuck whether anyone else does or not. If everyone else thought Calcutta was shit-hole, it wouldn't make any more of a difference to him than if everyone else agreed that it was the greatest place on earth. He is secure in his knowledge of the greatness of Calcutta, that's all that matters and he has no need for affirmation, flashy displays of affection... or even gushing raves in Durga Puja specials.