This is not about the A/B argument in Agile methods.
This is about get the elements of project scope sequenced in the right time order
- Does "A" come before "B", or not, and
- Is there a dependency between "A" and "B"?
- If not, then the sequencing question may be moot. If they are truly independent, then they can be scheduled for convenience, or according to some other dependency, "C"
Sequencing is the first task in forming a schedule, but only after you figure out the scope.
A before B
If you understand the nature of A and that of B, then if there is a dependency between them vis a vis time order, then getting A done before B sounds easy, but sometimes it makes you wonder!
- Is there a preamble to B that should be done before A is completed?
- Are the resources for A and B in conflict or not available; such could affect the "preamble" activity.
- Can B really start after A, or are there other dependencies on the start of B?
- Do I really want B to start, or do I want to pause and start C somewhere else?
- If I start B, immediately after A, have I introduced unnecessary risk or other impacts?
Schedule depends on sequence
So, if you're thinking about sequencing, you're probably also thinking about schedule: how long it's going to take?
Or, the other way around: if you are working on a schedule, you have to get the sequence down first.
From time to time, arguments boil up about scheduling tools, like MSProject and others. The usual thinking is that these tools are "so last century" and haven't kept up with more agile planning techniques.
And, worst of all, these older tools promote waterfall (gasp!) scheduling, which is demagoguery for finish-to-start precedence.
Finish-to-start precedence is a sequencing concept. If you pooh-pooh such precedence, I challenge you to put up the roof before the walls are in place.
It's all about the sequencing
First, you have to know what you are going to do. To wit: you can't sequence that which you don't know about, and furthermore, even then there may be sequencing errors you discover once you understand the full extent of the scope.
For any project, step 1 is to assemble (or define) the elements of scope by some affinity criteria. (Using the roof-after-walls example, get all the roof stuff in one grouping, and all the wall stuff in another grouping. That way, you can sequence the roof group after the wall group.)
Advice to PMO
At the PMO level focus on the major sequences that drive toward value-add milestones.
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