I often invoke uname -UK to collect concise information of my environment when e.g. filing bug reports and often forget which one is which. This is important when the two numbers do not match, as I often build and run kernels from different revisions while bisecting things, etc.

Also, users might assume that the order in which they are printed depends on the relative order the -K and -U flags passed to uname(1) on the command line, which is not true. Consider proposed change to the manual page.