Another opinion on using extreme programming for security

I found this excerpt from Matt Bishop's book, "Computer Security, Art & 
Science" very nice and wanted to share it.....

"Extreme programming is a development methodology based on rapid 
prototyping and best practices such as separate testing components, 
frequent reviewing, frequent integration of components, and simple 
design. A project is driven by business decisions, not by project 
stakeholders, and requirements are open until the project is complete. 
The design evolves as needed to remove complexity and add flexibility. 
Programmers work in teams or pairs. Component testing procedures and 
mechanisms are developed before the components are developed. The 
components are integrated and tested several times a day. One objective 
of this model is to put a minimal system into production as quickly as 
possible and then enhance it as appropriate.
Use of this technique for security has several benefits and several 
drawbacks. The nature of an evolving design leaves the product 
vulnerable to the problems of an add-on product. Leaving requirements 
open does not ensure that security requierements will be properly 
implemented into the system. However, if threats were analyzesd and 
appropriate security requirements developed before the system was 
designed, a secure or thrusted system could result. However, evidence of 
trustworthiness would need to be adduced _after_ the system was 
developed and implemented."

--
Mads