Chapter 5 is short and sweet so I don't have much to say. It gives some good guidlines for when it's a good idea to exchange. Basically, (probably obviously) you are looking to gain something with the trade, not just willy nilly throw pieces around. The thing he primarily seems interested in is a gain of time although of course there's the critical notion of trading off a piece which is doing some kind of work for the opponent. (He calls it a defender but is explicit that we should understand that in a very broad sense of the word.)
As with previous chapters, the text seems pretty straightforward. Interesting but not radically changing how I think about things. On the other hand the examples continue to be a mixture of enlightening and obscure, although tending to the obscure more than the enlightening.