anchor.diff:  
           let mutable garbage = [ ]
   
  -        for j in 0..100 do
  +        for j in 0..0 do // loop used for repeated testing in standalone executable
               let mutable totalMarkTime = 0.0
               let mutable totalEvalTime = 0.0
               let iter = 10
               for k in 1..iter do
  -                let root = Mod.init Trafo3d.Identity
  +                //let root = Mod.init Trafo3d.Identity
  +                let root = Mod.init 10
                   let mutable leafs = [ root :> IMod<_> ]
                   let rnd = RandomSystem(1)
   
  +                // configuration 1: average of 2-3 outputs, less depth
                   let depth = int (10.0 * pow 1.1 (float k))
                   let stdWidth = 1.2
  +
  +                // configuration 2: average 1-2 outputs, deeper tree
  +                //let depth = int (10.0 * pow 1.5 (float k))
  +                //let stdWidth = 0.3
  +
                   let mutable nodeCount = 0
                   //Log.startTimed "Create Tree: Depth=%d StdWidth=%.2f" depth stdWidth
                   for i in 1..depth do
  
positive.code: 
                  let markTime = (float swMark.ElapsedTicks / float Stopwatch.Frequency)
                  let evalTime = (float swEval.ElapsedTicks / float Stopwatch.Frequency)
                  Log.stop " MarkTime=%.2fs EvalTime=%.2fs" markTime evalTime
  
                  totalMarkTime <- totalMarkTime + markTime
                  totalEvalTime <- totalEvalTime + evalTime
  
negative.code:                 let swMark = Stopwatch()
                  let swEval = Stopwatch()
              
                  //Log.start "Depth=%-3d StdWidth=%.2f Nodes/Leafs=%-11s" depth stdWidth (sprintf "%d/%d" nodeCount leafCount)
                  for i in 1..runs do
                      if i > 5 then swMark.Start()
                      //transact(fun () -> Mod.change root (Trafo3d.Translation(V3d(i, i, i))))
                      transact(fun () -> Mod.change root i)
                      if i > 5 then swMark.Stop()
  
                      if i > 5 then swEval.Start()
  