Hi Eric,
Although the order of a Set is not guaranteed, this is not the same as saying that a Set is always random (for example, TreeSet is a set whose order is guaranteed to be sorted). And as I pointed out, the method IXWire.getAbstractPins() returns a set, but this is guaranteed to return the 'start' pin first.
However, if you have found that getWireEnds() does not always return the start pin first, then you will have to use one of the alternative methods.
Regards,
Simon