Difference between comparison-type values: case-sensitive and refer-case-sensitive

Hello

 

I followed last TechTalk on HMR. And the folowing paragraph is an extract from slide 30:

 

If the other constraints match (SIP message type, method name, parameter exists, etc.), the match-value is checked based on the configured ‘comparison-type’

•  case-sensitive and case-insensitive compare the string in match-value against the item, using string comparison

•  refer-case-sensitive and refer-case-insensitive compare the referenced value in match-value against the item, using string compare

I read HMR guides and other acmePAcket documents, and I still do not understand the difference between case-sensitive and refer-case-sensitive. Curerntly I'm using SC C6.0 version, and only case-sensitive value exists. Could you help me to better understand the different behavior between those both values?