Indeed. Also, it seems to me that the communication involved in the development of a poly relationship can often make boundaries much more real and tangible, indeed, because it's something the people involved need to talk about, rather than (most) 'conventional' relationships, which tend to run on unspoken and undiscussed concepts of monogamy. It took a few goes for me to fully realise the importance of that kind of communication, and I think perhaps that a poly relationship, because of its nature, is particularly good at teaching the importance of that.