> Wouldn't it have been better for them to ollow him for a while before apprehending him, then maybe he'd have inadvertantly led them to her?
Maybe. But they stood the risk of losing him, prompting him into some drastic action or simply taking too long. Clearly they thought apprehending him was the better option.
As for naming him, unlike the Christopher Jefferies/Jo Yeates case, this time he's been named on the BBC who are pretty wise to the pros and cons of this. I'm sure there is a very good reason for naming him.