Who is Tsai Wo from The Analects and what is their importance?

Tsai Wo is a disciple of Confucius. He is the most criticized disciple by Confucius. The Master criticizes him for the answers he gives others and for napping during the day. Confucius is particularly critical of his napping and speaks about carving rotten wood and troweling dried dung in reference to him. The Master does credit him with changing Confucius' idea of trust in the words one says to observe one's deeds first. Tsai Wo wants to shorten the mourning period for one's parents from three years to one, for which Confucius thinks he is unfeeling. Regardless of criticism Tsai Wo has limitless admiration for Confucius.