[Cake] triple flow isolation

[Jonathan Morton]

> On 14 Jan, 2016, at 16:20, moeller0 <moeller0 at gmx.de> wrote:
> 
> I am really curious how cake behaves in that setting...

I have identified a limitation in the current triple-isolation implementation - in fact it only works properly if the sources *and* destinations of the flows are independent.  I’m working on a fix, so that it also works when *either* are different.

Turns out that a brand-new, state-of-the-art algorithm has some subtleties to it.  Who would have thought.  :-)

 - Jonathan Morton