Not picking on your comment, just wanted to share a little anecdote. We had this one retired guy in grad school who already had 2 Ph.D.s in other disciplines and this was probably his third. OMG he would incessantly ask questions in class. They were not even helpful questions -- very basic and mundane. In an algorithms class he asked the prof. how he came up with those numbers in an example even though he had already said that they were random. At which point the prof. rolled his eyes and said "magic!"
His actions were very annoying and slowed down the class significantly by breaking the flow. When asked privately why he would do that his answer was he was helping out others who may be too afraid to ask basic questions. I felt like banging my head on a wall.