Jeu --
There would be several requirements that you would need to meet before you
could do this:
1. The Project Server administrator would need to create a custom
enterprise Task field that you could use to denote the tasks in question. I
personally would use a Flag field for this purpose. After the field is
created, your PMs would need to open every project, apply the Gantt Chart
view, insert the new custom Task field, set a Yes value for every one of
thos special tasks, and then save and publish their projects.
2. You would need to create a master project that represents the programme,
and include the projects you need to see as subprojects. You would need to
save and publish the master project.
3. Your Project Server administrator would need to create a custom Project
view in PWA that includes the custom enterprise Task field, along with other
Task fields users need to see. In the View, the Project Server
administrator would need to include a Filter that filters on that custom
Task field.
4. Users can access this custom View by navigating to the Project Center
page and clicking the name of the programme.
Hope this helps.