It is better that we split 'protect' right rather than using '$wgCascadingRestrictionLevels':
1- 'protect': Change protection levels
2- 'editcascadeprotected': Edit cascade-protected pages (exactly like 'editsemiprotected' and 'editprotected' rights)
Change protection levels and edit cascade-protected pages are two different concepts.
Version: 1.24rc
Severity: enhancement