Is it true that guide books advise you to avoid eye contact with passengers in the Paris metro?

Underground Etiquette -- See Lesson 23 -- Avoid Eye Contact:

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This is amazing. I quote this from your source, even if I suspect it is ironical (you never know with the British):

"Even the mayor Ken Livingstone knows this one. Do not look at anyone while you're on the tube and do anything to avoid eye contact. Fiddle with your watch like Ken. File your nails like the lady next to him. Read the ads (why else are they there???). And remember what Andrew Martin former writer of Tube Tales in ES magazine said: "It is absolutely not acceptable to make eye contact on the Tube. If God had meant us to look at our fellow traveller, he would not have invented the Evening Standard." The reason you must avoid eye contact is to avoid nutters. The minute you make eye contact with a nutter he or she will insist on talking to you and you will become the centre of attention on the carriage because you may end up talking to the person and as we all know .....talking on the tube is strictly forbidden."

A quote related to the Paris metro:

"There are many talented and also enterprising individuals who use the Metro system to gain a few euros, either through busking (acceptable by the authorities), busking with begging (not encouraged and frowned upon), or just begging (not condoned). There are some fantastic busking talents out there and the Metro often comes alive with their music, so by all means drop them some change as you go by. But there is a difference between a talented busker and someone pushing you to donate for causes unknown at the end of a "performance", especially when these individuals board the train and try to catch your eye during the act. Avert your eyes, avoid all eye contact or they'll single you out. I carry around a French magazine or novel, to look more like a local and appear engrossed in my reading when on the trains. The French generally ignore them."

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