Forum:KB:Force Lightning Awareness

Why did'nt Yoda inform Luke about Force Lightning and how to counter it? Their is a huge,almost 100% chance that the Emperor would employ it offensively and having Luke unprepared would have screwed everything. Also what things did Luke learn in his training and how long did he spend on Dagobah? NOTE: This is a three-part question.23:05, January 3, 2012 (UTC)