A partial lifting of the ban will encourage use of all electronics in airline cabins, from the moment boarding begins. And while some scientists may be O.K. with tablets and readers rather than phones because of how such transmissions may affect the cockpit, these battles shouldn’t be fought on the front lines — in airplane cabins where proven safety procedures can save lives. “I don’t have time to argue the whys and hows of the policy,” says Heather Poole, a flight attendant and author of Cruising Attitude. “The press never mentions how these PEDs might affect evacuating quickly when time is critical.” Since departures and arrivals are so critical (most fatal accidents do not occur during the “cruise” portion), and since even the worst crashes have become increasingly survivable, the need for all passengers to stay alert and aware is critical. It’s not the time for one more Tweet.