It's really hard to get gaffertape version 3.0 out the door. Those best practices are ultimately about reducing wear and tear on the development team, so you can keep momentum for a long long time.
But since you can make pretty much any development strategy work for about 18 months, by the time the consequences are felt either those people are gone or nobody still there can paint a clear cause and effect story.
Which is the text book explanation, but you can gaffatape and still do SOLID, making everything easily replaceable later on.
The key feature of gaffatape programming is that it gets shit done, to make sure you're still around to do a 3.0 release.
The key downside of gaffatape is that it requires better talent, because your programmers need to know how to hack it in a way that won't ruin your codebase.
But since you can make pretty much any development strategy work for about 18 months, by the time the consequences are felt either those people are gone or nobody still there can paint a clear cause and effect story.