I use TEDICT, an app that you can type scripts a speaker talks, to hone my listening ability. I have just finished one of Dan Ariely's presentations, it was long but I have seen it on TV before so the content was familiar to me. Good thing is he doesn't talk so fast, but some speakers speak very very fast and the script includes a huge amount of words with the same length of a speech. I wonder they are just trying to put all their ideas into the time, or they are too smart and cannot speak slowly. I had ex who tends to speak super fast and he explained even his tongue can't catch up with the brain. This is another one Daigo was saying in the video. He is of course much smarter and illustrates better.