I fear you halfway missed what I meant. I was not talking about UML tools. I was saying that there are good reasons to program in a way where you do not start with final specs, and there are many cases where code is incrementally rethought and redesigned as you go. In particular it is not sufficient to say as a hard rule that people should always have solid specs up front.

For two very different references showing that what I am talking about is not just "do not plan" under different words take a look at Extreme Programming and Rapid Development by Steve McConnell. The first is a specific methodology that uses incremental planning and refactoring. The second is a survey of best practices for producing software, chapter 7 in particular contains comparisons of different lifecycle planning techniques and the tradeoffs you make in choosing them. Most of the options discussed follow some variation on ready, fire, aim.

As for magic bullets. I disbelieve there is a magic bullet. There are a lot of incremental improvements. Put them together and you get order of magnitude improvements, but anyone who is saying their technique can solve all of your problems is selling something you probably don't want to be buying...