How to spot a food critic

From an interview with Ruth Reichl.

There are very few food critics you can’t find a picture of. Go on the Internet and circulate them to your staff. I went out with a big deal critic this week, and I was kind of stunned that he was not recognized in the restaurant we went to. His picture is everywhere.
There are a few really obvious things. If you’ve got a four-top and you’ve got four different appetizers, four different main courses, and four different desserts, probably you’ve got a food critic there. Usually two people will want the Steak Diane, or something.
If people are passing the plates around, see who they’re going to. Every critic has to taste everything on the table. A sharp-eyed waiter will notice people are actually passing plates around or passing a bread plate with a taste to one person at the table.
I never got up and went to the bathroom, because it was another opportunity for someone who is not my waiter to spot me. But most critics go to the bathroom to take notes. If someone is going at the end of every course, it may be a giveaway that it’s a critic.
Another sign is if you see someone coming in twice at a time when no one wants to eat. When you’re a critic, if you can go at 5:30 you go at 5:30, and if you can go at 10:30 you go at 10:30. If you see the same person come in twice at 5:30 or 10:30, take a look at them. Why are they agreeing to come at odd times? Especially early reservations are a good giveaway.

All of us who aren't restaurant critics can read this as "how to impersonate a food critic."

However, in this day and age of Yelp, the real answer to the question of how to spot a food critic is to open your eyes. Everyone's a critic. It's no longer necessary to pretend to be a food critic to receive attentive service. It can be a bit much, these often entitled trauma narratives disguised as restaurant reviews on Yelp, but it's progress that discriminatory service is less of an issue.

This, from Reichl, seems like just sensible advice in general for dealing with criticism in this age since you can take slings and arrows from any direction if you so much as set up a presence on the internet.

What would you say to a restaurateur who’s thinking about responding to a bad review? 
I would follow the Danny Meyer model. Good review or bad, I never wrote a review that Danny Meyer didn’t send me a personal note, always thoughtful and not defensive. If it was a bad review, it was thank you for pointing this out, and I’ll deal with it. If it was a good review, he always added something to it. I think you have nothing to lose by writing a thoughtful note or response to a critic. You have everything to lose by writing a nasty note. The nastier the note you write, the more it will be picked up by social media and the worse it will be for you. No matter how angry you get about it, imagine a million people reading your response. Whining gets you nowhere.