Lucas did not think of Dooku until he began AOTC. Looking back, we can safely say that Jedi Master Dooku was away on assignment, while Qui-gon was speaking with the Council. Jedi are busy people. Mace: "I'll gather what Jedi are available..." The opening crawl also mentions that the Jedi are overwhelmed and spread thin. TPM showed that Obi-wan and Qui-gon were on assignment. AOTC began with Anakin and Obi-wan coming back from Anison. They're always on the go. Dooku was off world and not important to the plot then. If Lucas feels the need to put him in, he will. But answer me this, where was Lando in ANH? He's important to the plot in ESB and ROTJ, but why didn't we see him before then? Yarael Poof was caught in the crossfire between Jango and Zam, and another foe. Poof was killed by the latter. Coleman Trebor replaced him on the Council. Eu is canon, to a degree. In that it's a parallel universe and thus happened. The movies still come first, but the story of Poof is wrapped up there. And if that doesn't satisfy you, he died off screen. All but two fully trained Jedi survive the Clone Wars and the Jedi Purge. Yoda was defending himself, not attacking Dooku. Dooku was the one to suggest using the Lightsabers. He just obliged him. As to Sifo-Dyas, I said that nothing more will be revealed until episode 3. How or why, will not be known until then. It could've been Maul or it could've been in the line of duty. If it's the latter, then that's it. Palpatine just used it to his advantage. Jedi do die, without needing a Sith Lord. Anakin: "No one can kill a Jedi." Qui-gon: "I wish that were true."