It would be to transmit ideas, start conversations, rekindle the nuance and dialogue that has been largely lost to appeasing the social gods.
This presents an intriguing conundrum.
Having your own blog, an independent platform, means that you have the luxury and freedom to choose what appears on your own /required page. But what to choose?
I was looking at it from a more personal angle: this is me as a blogger, as a person, and this is what you need to know to understand me and what I'm doing.
Dave, I feel, is approaching it in a wider context: this is me, this is what I think about, and this is what I think you need to be aware of to understand where I'm coming from and to tackle it head on.
Now, as we've seen over the past 18 months or so, people's ideas, opinions and beliefs will differ, and there will always be polar opposites, but Dave is advocating the need for more considered discussion in greater than 140 characters - perhaps soon to be 280 but it's still nowhere near enough.
As Manton Reece says in his reasoning for choosing 280 characters for micro.blog: going longer than 140 characters gives you a bit more room for expression, for clarification, so that your point does not become so distilled or misinterpreted in the drive for ultimate brevity.
There's no guarantee, of course, that more words means greater understanding or willingness to communicate with those who maintain alternative views, but it does remove an artificial limitation and at least give us a fighting chance.