Talk:Skill Trees
From Seed
It looks like the formula has changed to:
Training Time = (2^level) * 300 * (difficulty^3)
http://www.seedthegame.com/forums/showthread.php?p=15973#post15973 is the reference!
It looks like training Electrician 5 opens up Advanced Electrician. I would have put it in, but I thought I might break the layout...