I don't know why but it just never clicked.  You can use regular expressions as the labels on your branch step even when evaluate labels is false.  A simple example is checking the http status values from a RESTful call:
 

• Branch header->status
  • /^2[0-9][0-9]$/ (OK)
  • /^4[0-9][0-9]$/ (Non retry enabled error)
  • /^5[0-9][0-9]$/ (Retry enabled error)

Much easier than trying to list all combinations.