Earlier quoted context omitted.
"Twitter encourages and amplifies bad behavior while inhibiting intelligent and thoughtful conversation." Ok. So, how is Twitter unique here? How often do you read an intelligent and thoughtful article in your local newspaper? Doesn't your local cable news channel choose to focus on the 'bad' instead of the 'good'? Or are you living in some alternate universe?
The 140 character limit and general focus on brevity encourages people to drop specificity and shift to bold proclamations and absolutes.[1] This is guaranteed to cause miscommunication and hurt feelings. The resulting arguments are impossible to effectively reason out at 140 characters. And even if you do work it out in another medium (email, phone call, etc) - the re-tweeting spreads the old arguments like wildfire…
It's a scary thought that the opinions of society can be clustered by similarity of Twitter newsfeeds. That sounds ripe for manipulation and propaganda dissemination.