I know I have wondered this from time to time as well.
The answer is yes, you can take a ticket and add it as a task on a waterfall project plan. This can be accomplished by checking out the project plan-->clicking on tickets tab within the project plan-->locating the appropriate ticket using the search-->then drag the ticket over to the appropriate plan over to the right. Once the task is on the plan, you can move it around as needed. I hope this helps/makes sense!
Gosh Marcus, I am always blown away by your mature and inquisitive questions, keep up the good work!!