> Boeing) has been doing this for a long time Sure, and Microsoft has been using formal methods for eliminating all manner of security holes since at least the

> Boeing) has been doing this for a long time Sure, and Microsoft has been using formal methods for eliminating all manner of security holes since at least the XP SP2 days. I didn't say that formal methods were always a bad trade off. I said that they are very expensive and implied that they are a bad default tradeoff for general purpose tools to make.