You only need recognition-memory to use Web and GUI interfaces, whereas you need recall-memory to use command line interfaces and scripts, which is far more difficult. That's why clicking in a Web GUI or graphical XML-generator replaced scripting. You need a lot of previous information in your memory for recall to write stuff like the following example taken from your linked page:

  def project = 'quidryan/aws-sdk-test'
  def branchApi = new URL("https://api.github.com/repos/${project}/branches")
  def branches = new groovy.json.JsonSlurper().parse(branchApi.newReader())
  branches.each {
    def branchName = it.name
    job {
        name "${project}-${branchName}".replaceAll('/','-')
        scm {
            git("git://github.com/${project}.git", branchName)
        }
        steps {
            maven("test -Dproject.name=${project}/${branchName}")
        }
    }
  }

The vocabulary and grammar in that script is quite complicated and people would rather be presented with the options for clicking on a web page. But perhaps you're promoting a particular software product?

GUIs are more discoverable than command lines. Text files are easier to save in version control. So it's common to have a system where the GUI hooks new users, but they eventually have enough configuration in it that the GUI is no longer a reasonable way to control it all, and they need a way to extract the information in a reasonable format. Hence the reason several Jenkins plugins have evolved to do that.

I also used JobDSL, and thought it worked pretty well. I don't think my teammates agreed, they seemed to just want to change things in the UI and this was just something getting in the way of their work. Some were willing to learn it, others weren't interested.

I think the new Jenkinsfile approach looks very promising: http://jenkins-ci.org/content/pipeline-code-multibranch-work...

We do similar thing but with workflow plugins.