Portfolio roll-up across projects

Three projects each at P80 are not a programme at P80 — the latest one finishes the portfolio, and the costs add. The roll-up resamples each project's stored distribution (4,000 draws, fixed seed) rather than naïvely adding percentiles, and treats projects as independent parallel programmes until you say otherwise.

1. Run project A, add it. With a completed run on screen, click Portfolio in the top bar, then + Add current run.
2. Repeat per project. Open the next .riskproj, run it, + Add current run again. Each row records the project's fitness verdict, P80 finish, P80 cost and contingency.
   Completion is the latest project; cost is the sum — both from resampled distributions, not percentile arithmetic.
3. Model the shared driver with Systemic ρ. Independence is the documented default — but a common contractor, labour market or currency moves projects together. Slide ρ up and the drawer compares against the independent case. (Note the directions: shared upside/downside makes portfolio completion distributions tighter at the top but the cost tail fatter — the drawer explains as it goes.)