Yoda:- used anger or concentration
When Yoda and Sidious were locked in the "lightening v absorb" battle, Yoda seemed to get mean before he blew Sidious (and himself) away.
Did he use a bit of anger to give his power a boost or was it just more concentration?
Sidious certainly looked suprised and Yoda probaly had some experience of the Dark side otherwise his Blocking obsorbing trick he wouldn´t have learned.
I disagree... the Jedi do at times let their emotions influence them when they fight. Remember how upset Obi-Wan got when Maul killed Qui-Gon. Remember how emotional Obi-Wan was when he fought Anakin? How emotional Luke was both times he fought Vader? The difference is that they don't let the emotions take over... they resist them. I think it would be hard for Yoda not to be pissed at the man that killed the Jedi Order that he had worked hard to preserve all his life, including all those younglings. But he did not let such emotions overtake him.
There's a difference between having emotions and using emotions. Obi-Wan can be as pissed and miserable as he wants about Qui-Gon dying or Anakin falling, but as long as he doesn't use them, he's fine.
Though, from what I've read, several people think that Ben was skirting the Dark Side in his fight with Maul, after Qui-Gon went down.
i think with yoda hed gone past desperate and he knew this was it. he had to use everything he had to survive. you can see just before it he was looking away barely holding on and id say that he realised that if he was every going to summon enough strength to fight the sith this was it. like when you work out, you make agressive looking faces when you push yourself hard enough. i think that combined with the knowlege that this was his last moment to make a difference in the fate of the galaxy. determination plus massive amounts of effort.