Looking to understand how to group a set of tasks

How can I set a group of subtasks such that OmniPlan treats them as one solid block of tasks: no other tasks can be scheduled inbetween these subtasks once this block of tasks is entered?

If A and B are tasks, and A and B have subtasks A1, A2, A3, B1, B2, and B3. How can I make it such that once one set of subtasks are started that they are all completed before another set of subtasks are started?

There is no dependency on A starting before B, or B before A. I don’t care which task starts first, I just want all of its subtasks to be completed before the other task is started.

I have many of these scenarios and so am trying to understand how to set this up. My only thought is that I am becoming too granular when I get to the subtasks (A1, A2, A3 and B1, B2, B3). But I really want to track execution of them.

Advice?

If you don’t care which task starts first, you can force what you need by creating a dependency from one group to the other group. Just choose one to be the first.

Yeah, I know I can do that but it creates a false dependency that may result in a non-optimal schedule. I think my problem is that I am expected to just stop at the last contiguous block of work (task level in this case). If my sub-tasks need to be completed as a block then I gather I should just ensure that (using your diagram above) “Group A” and “Group B” just include the effort required to complete the subtasks (and then delete the subtasks).

Basically, that is what I am saying when I say that they need to be created as a block: that the last task is a continuous block of work. Only my anal-retentiveness makes me want to break it down further so I can track progress :-)

I was just wondering if there was a way of me to mark a set of tasks as “contiguous” without having to set false dependencies on other work.

But thank you for your response. It does confirm that I am taking the detail too far.