My take, is that this primarily attempts to address one of the key criticisms of use cases - the granularity issue. Use cases are often too broadly written ini

My take, is that this primarily attempts to address one of the key criticisms of use cases - the granularity issue. Use cases are often too broadly written initially. When examined closely, one discovers that that the use case presented really needs to be broken down into many more detailed (and changed) cases. The introduction of "slices" appears to acknowledge that. The problem is that like functional decomposition in structured programming, constant re-arrangement of the functional "tree" representing the problem will likely result.