The crucial bridge between theory and practice is called execution - http://abdullin.com/journal/2012/2/22/importance-of-execution.html

Analysis for Continuous Delivery: Five Core Practices

1. Start with a minimum viable product (MVP).
2. Measure the value of your features.
3. Perform just enough analysis up front.
4. Do less.
5. Include feature toggles in your stories.

http://www.informit.com/articles/article.aspx?p=1829417

Discussion about various issue when thing change - http://swreflections.blogspot.com.au/2013/01/frankensystems-half-strangled-zombies.html

http://www.opsbs.com/2013/01/good-and-bad-patterns-in-development-and-operations/

http://www.yegor256.com/2015/06/08/deadly-sins-software-project.html