My own take on it is different again - as far as I see it the job of technical lead on a project is take ensure that the right technical decisions get made and to ultimately take responsibility for those decisions. Yes, I could directly override people and tell them to do things - but if I ever did that then IMHO I would have failed.

A lot of my job is asking questions, making suggestions and proving (when necessary) that something can actually be done. [I love it when someone utters a phrase starting "There is no way to...."]