>These are the guidelines for us researchers who are not at all legal experts and still need to use quotes and refer to other people's work in our own. I think the key phrase here is "the length of the quoted passage and the use to which it is put should be fair to the author and publisher". We are using the material here for learning purposes, and as far as I can see, people who use extraneous material on this site provide sources and references alongside. Both of these seem to me to be quite "fair" practices.

I agree Marianna. I think that short quotes are probably fine and that when we use them they should be acknowledged, as they are at present, in most cases.