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Inch-Pebble Project Scheduling: Managing Concerns (#3 in the series How to Use Inch-Pebbles When You Think You Can’t)
By Johanna Rothman

If you’re working on a project where inch-pebbles are useful, consider why people resist using inch-pebbles.

Many people, project managers and technical staff alike, resist defining inch-pebbles. They may not be sure which project to start using inch-pebbles on. They may be concerned they will not see any return on the time they invested defining the component tasks.

Since not everyone is willing to try using inch-pebbles, recognize people’s concerns and the consequences of those concerns. You can then choose a multi-pronged approach in addressing their concerns.

Table 1: Possible concerns and consequences from using inch-pebbles

Concerned Person Possible Sources of Concern Perceived Consequences From The Concern
Technical staff Senior management or project management will micro-manage them. They might lose some freedom to plan their work
Project Manager Senior management will try to micro-manage the schedule. The project manager might lose her freedom to organize and replan the project where necessary.
Technical staff and Project Manager It takes a long time to develop component tasks. Project staff could feel that they are late before they start. Senior management may pressure project manager to “just get started”
Technical staff and Project Manager They may find more tasks to do during planning. They might be late before they start, especially if they committed to a date before generating the detailed schedule. They might lose flexibility to reorganize and plan their work and may feel pushed to just get started without planning.

Table 1 lists some common scenarios. Most of these scenarios deal with loss of freedom to the do the job, and to manage your own work. Below are some ideas to deal with the concerns about loss of freedom and flexibility to organize and manage the work:

Micro-Management Concerns

No one likes to be micro-managed. After all, we’re professionals. It’s hard to believe at first, but inch-pebbles can actually free you from project micro-management. Because you define the tasks in small increments, and a task is either complete or not, there is no need for continual status and task checking, for micro-management. Project status is obvious at any time in the project. (If you’re working with a project manager or senior manager who inflicts help, inch-pebbles can’t save you – but then nothing can.)

Can Planning Make You Late Before You Start?

I’ve only met one person who over-planned a software project. He was stuck on what the project should deliver, and took too much time before deciding what the product should deliver. Most projects run into trouble from under-planning, the planners miss tasks such as rework or in-process testing. Table 2 shows an example of the difference in planning a simple task, creating a specific module for an application, the “normal” way and the inch-pebble way.

In this case, the implementer was off by 50% in his original estimate. He had simply forgotten some tasks in his original planning.

Table 2: Original task time compared with Inch-pebble task time

Original task Original duration Inch-pebble component tasks Inch-pebble duration
Develop module1 14 days Verify module1 design with hardware group 1 day
Implement the code and compile without warnings for functionality A, B, C. 2 days for each piece of functionality 6 days
Develop unit tests for A, B, C 6 days
Test module1 with pilot hardware, rework. 2 days per cycle, plan for 3 cycles 6 days
Peer review with module2 developer 1 day
Check the code into the mainline 1 day
Develop initial documentation 2 days
Have module2 developer review documentation 1 day
Build the test system 1 day
Verify module1 within the entire test system 2 days
Run acceptance tests 1 day
Total 14 days 28 days

Flexibility of Planning and Working

I have found that I have the most flexibility in planning my work and the work itself if I spend more time on the planning part of the project. When I take the time to plan in detail, I frequently have ideas about how to shorten the critical path. By using inch-pebbles, you and the project team will be able to orchestrate your work, and maintain a very short release cycle.

This article is an excerpt from the article “How to Use Inch-Pebbles When You Think You Can’t”, which can be found at:

Johanna Rothman consults, speaks, and writes on managing high-technology product development. Johanna is the author of Manage It!’Your Guide to Modern Pragmatic Project Management’. She is the coauthor of the pragmatic Behind Closed Doors, Secrets of Great Management, and author of the highly acclaimed Hiring the Best Knowledge Workers, Techies & Nerds: The Secrets and Science of Hiring Technical People. And, Johanna is a host and session leader at the Amplifying Your Effectiveness (AYE) conference ( You can see Johanna’s other writings at

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