none
Question about linking summary tasks RRS feed

  • Question

  • Dear all:

    Hi. I've heard several times that it is not a good practice to link summary tasks in a Gantt file, is that true or false?. In fact I think it is beneficial to link summary tasks especially if those tasks are phases (for example: Initiation, Planning, Execution and Closing).

    Thank you very much

    Best regards

    Carlos Negroni

    Thursday, May 2, 2013 10:12 PM

Answers

  • Carlos --
     
    Linking summary tasks is generally not a good thing, as this can lead to a circular reference error some day in your project.  Since the process of resolving a circular reference error is tedious and difficult at best, we recommend that you avoid circular reference errors by not linking summary tasks.  Instead, in a scenario like you describe, we recommend that you link the final milestone in each summary section with the first task in the next summary section.  Hope this helps.
     

    Dale A. Howard [MVP]

    • Marked as answer by CNegroni Thursday, May 9, 2013 11:56 PM
    Thursday, May 2, 2013 10:59 PM
    Moderator

All replies

  • Carlos --
     
    Linking summary tasks is generally not a good thing, as this can lead to a circular reference error some day in your project.  Since the process of resolving a circular reference error is tedious and difficult at best, we recommend that you avoid circular reference errors by not linking summary tasks.  Instead, in a scenario like you describe, we recommend that you link the final milestone in each summary section with the first task in the next summary section.  Hope this helps.
     

    Dale A. Howard [MVP]

    • Marked as answer by CNegroni Thursday, May 9, 2013 11:56 PM
    Thursday, May 2, 2013 10:59 PM
    Moderator
  • Linking summary tasks is not a best practice.   Creating links between summary tasks may cause circular relationships.  It may also cause file corruption.

    Create milestones "Initiation complete", "Start Planning Phase", "Planning Phase Complete", etc.  Link as appropriate to ensure that Initiation Complete is the successor to the Initiation tasks.  Link Initiation Complete to the "Start Planning Phase" milestone.

    Thursday, May 2, 2013 11:27 PM
    Moderator
  • We've had this discussion amongst the MVPs before and I think the final advice was, for beginners and even intermediate users, do not link summary tasks. However for more advanced users, where one group of tasks must follow another and the order of tasks may change, linking the summary tasks is a much simpler communication. I do it regularly. The alternative is to monitor task sequences weekly and re-link as necessary or add many links. One leads to inaccuracies, the other to a messy communication.

    Rod Gill

    The one and only Project VBA Book

    Rod Gill Project Management

    Friday, May 3, 2013 10:05 AM
    Moderator
  • Critical path calculations don't work so well with linked summary tasks.

    Reid McTaggart – DeltaBahn Vice President
    Blog | Twitter | LinkedIn Please click Mark As Answer; if a post solves your problem or Vote As Helpful if a post has been useful to you. This can help other community members reading the thread.

    Friday, May 3, 2013 3:34 PM
  • Never had a problem with them before and for many projects I'm more interested in the communication from my schedule. A schedule with too many links confuses. If linking summary tasks creates a simpler and more effective communication I do it.

    When communicating the critical path is important, I do a CP audit that shows up any potential problems.

    Primary goal of a schedule is to "communicate how the project will be successfully completed". So identify the most important communication needed for your project and then create the best schedule that does it.

    But as I said it's good for experienced schedulers only.


    Rod Gill

    The one and only Project VBA Book

    Rod Gill Project Management

    Friday, May 3, 2013 10:32 PM
    Moderator
  • I link summary tasks when the tasks under the summary tasks are self contained; meaning no links from outside the summary tasks into, or out of, a task under the summary task. Once you have links directly to a subtask, you have to be careful. As stated before, troubleshooting circular references is problematic.

    This process is very helpful when you have a single resource doing all the tasks under the summary task, but the tasks have no hard dependencies -- they can  be done in any order. Rather than link all the tasks based on resource constraints, they are all listed under the summary task and then the schedule is resource leveled. The tasks get spread out based on resource loading, and you get rid of the hassle of breaking and reconnecting links when the order of task execution changes -- based on the phase of the moon, what was for breakfast, etc...

    Tuesday, May 7, 2013 7:23 PM
  • Hi:

    Thank you very much for your answer Dale, so I guess that if I’m not going to use Subprojects (and if I'm not going to have links entering or going outside from the tasks inside the Summary tasks) then it could be fine to link summary tasks.

    Best regards

    Carlos Negroni

    Friday, May 10, 2013 12:03 AM
  • Carlos --
     
    Thanks for the follow up question.  Three factors than can cause a circular reference error are:
    • Linking summary tasks across subprojects in a master project.
    • Links on both summary tasks and subtasks below a summary task.
    • Link lines that go both directions in your project, going down and going up, on summary tasks.
    If you are avoiding the first and second items above, then I would recommend you avoid the third factor as well.  As best as you can, make sure your links always point downstream in your project, creating a waterfall effect, and you should be fine.  Hope this little extra helps.

    Dale A. Howard [MVP]

    Friday, May 10, 2013 12:24 AM
    Moderator
  • Dale,

    Unrelated to this particular post but sometimes when I try to view your replies, they don't show up. The forum list shows that you have a reply but when I open the thread, there is no response from you, only the original post. This has happened twice today and once several weeks ago. It seems to occur when you are the only responder. Are you entering your replies differently?

    I've tried two different browsers do I don't think the issue is on my end.

    John

    Friday, May 10, 2013 2:58 AM
  • True John, even I'm facing same issues viewing Dale's responses.I also tried checking on IE, firefox, chrome - but none worked.

    Sapna Shukla

    Friday, May 10, 2013 9:01 AM
    Moderator
  • John --
     
    Nope, I have not changed anything.  I am using Windows Live Mail with the Community Forums NNTP Bridge software because I like the user interface much better than the web interface in IE.  When you look at this thread, if you click the drop down arrow to the left of the initial post, I believe you can see my responses.  But if you click the name of the original post, that is when you cannot see my post.  Correct?  Let me know.  Thanks!
     

    Dale A. Howard [MVP]

    Friday, May 10, 2013 11:58 AM
    Moderator
  • I'll chime in too.  I am now seeing your posts - but there have been several occasions where I see your name posted as a reply - but no posts appear.  My guess is a hiccup in the NNTP bridge post.
    Friday, May 10, 2013 12:59 PM
    Moderator
  • Dale,

    Well, I'm glad I'm not the only one who has had a problem. Tell you what, I'll post a test message for your response only. Then when you respond I (we) can all try the down arrow (expand) method of opening, assuming a normal click on the message title doesn't show your response. I'll let you know how it works.

    Thanks,

    John

    Friday, May 10, 2013 2:41 PM
  • Hi Dale:

    Thank you very much, I'll have this in mind (after all I like to link summary tasks specially when they are secuencial and you are not dealing with subprojects).

    Best regards

    Carlos Negroni

    Thursday, May 23, 2013 11:43 PM
  • Carlos --
     
    You are more than welcome for the help, my friend!  :)
     

    Dale A. Howard [MVP]

    Friday, May 24, 2013 2:12 PM
    Moderator