Say you have some text 'AAABBBCCCDDD' and there are 2 fix its on that text. Fix-it A just wants to remove all occurances of 'C' and fix-it B wants to replace the entire string with 'XXXXXXXXXXXX'.
These 2 fix its currently get diagnosed as conflicting, and prevent the entire fix it from applying(plus any from the same warning).
However Fix-it A can be disabled (while leaving any other fix its in the same warning active) without causing any conflicts.
Note I haven't included any specific test cases, but running the clang-tools unittests and regression tests yielded no failures.