Status: In Review
On Jenkins 1.580.2, as per http://htmlpreview.github.io/?https://github.com/jenkinsci/jenkins/blob/master/core/src/main/resources/hudson/triggers/TimerTrigger/help-spec.html, I am expecting
H/15 * * * *
to generate random times depending on the project, but to run every fifteen minutes.
This works fine for builds, but not for polling, as you can see on the included image.