Top Rank Node is not center aligned over some subgraphs

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4

Not sure why the mis-alignment, but enclosing Plan in a cluster seems to work.
If not we can look at Osage.

pleaseCenter2
pleaseCenter22107×231 17.8 KB

digraph "ISO 9001 - Orientierung am PDCA-Zyklus" {
  fontname="Arial,Helvetica,sans-serif"
  node [fontname="Arial,Helvetica,sans-serif"]
  edge [fontname="Arial,Helvetica,sans-serif"]
  graph [
    //newrank = true,   // probably not necessary
    nodesep = 0.4,      // ok
    ranksep = 0.25,     // ok
    //overlap = true,   // ignored by dot
    //splines = false,  // not necessary, all edges are invis
  ]
  node [
    fixedsize = true,
    fontsize = 18   // 90,
    height = 1.1    // 5.5,
    shape = box,
    style = "filled, setlinewidth(5), rounded",
    width = 4       // 19
  ]
  edge [
    style = invis,
  ]
  subgraph clusterPlan {
  peripheries=0

  subgraph Plan
  {
    node [color = "#22bb55"]
    plan [
      label = "Plan",
      height = .5  // 2.5,
      width = 17.2   // 4 * nodewidth + 3 * nodesep
      ]

    subgraph kontext {
      margin = 1       // ???
      kontext4_ [
        label = "4\nKontext der Organisation"
      ]
    }
    subgraph fuehrung {
      fuehrung5_ [
        label = "5\nFührung"
      ]
    }
    subgraph planung {
      planung6_ [
        label = "6\nPlanung"
      ]
    }
    subgraph unterstuetzung {
      unterstuetzung7_ [
        label = "7\nUnterstützung"
      ]
    }

    plan -> kontext4_
    plan -> fuehrung5_
    plan -> planung6_
    plan -> unterstuetzung7_
  }
  }
  subgraph Do {
    node [color = "#cc99aa"]
    do [
        label = "Do",
        height = .5    // 2.5,
      ]
      subgraph betrieb {
      betrieb8_ [
        label = "8\nBetrieb ",
      ]
    }
    do -> betrieb8_
    }
}