Should we manage the software development process as such with Six Sigma?

In an earlier article, I define three different relationships that companies have with information technology: A primary technology company creates new hardware and/or software, a tertiary technology company uses those products to support its own business operations, and a secondary technology company helps tertiary companies figure out the products offered by primary companies. The process of software development is a business operation in its own right only for primary technology companies; for all others, it is simply a support function. Any method that treats software development at the same level as a true business operation is going to miss the target to some degree.
We have shown that software development is not a manufacturing process in any case. We have also shown that software development is a business process only when the core business of a company is software development. For secondary and tertiary technology companies, software development is only a supporting activity, and not a business process in its own right. Finally, we have shown that the underlying philosophies of Agile development and Six Sigma management are different. The former seeks to minimize administrative overhead to leave professionals free to do the right thing, while the latter depends on formal documents, hand-offs, and abstract data analysis to enforce quality on a process from without. Therefore, the question of whether Six Sigma applies directly to an Agile software development process in a tertiary technology company is answered by the first row in the truth table.