Singing performers have an incredibly difficult task when you consider that, in an ideal world, their singing and acting would both be at the same high level of excellence. The reality seems to be that singing performers seem to come to the art of performance from two different starting points. The first group starts with acting training that then leads to singing as an additional skill to fill out what they have to offer. When push comes to shove acting and text intelligibility takes priority. The second group starts with voice training being the primary focus and acting being viewed as an additional skill they have to acquire.
For the first group preparing a dramatic monologue and monologuing a song should be relatively familiar. For the second group, in my experience, spoken dialogue can be the most difficult to learn and deliver naturally. This section is meant as a tool to help those whose primary performance skill set is rooted in musicianship. For those who started as an actor, this will be useful to think about in reverse. It will reveal to you what the composer was thinking and why they made the decisions they did. It will also help you become more sensitive to what the music is calling for.