Each person in each place at every moment has a unique perspective. Respecting this and finding ways to deal with this level of complexity is a real and important challenge. In DSRP, I think attention to perspectives is more critical to humanity that the other three. Put another way, attention to Distinctions, Systems, and Relationships to the exclusion of Perspectives is life threatening.
Differences in perspective arise naturally from differences (distinctions) in time, place, culture, identity, individual, group, mood, experience...