Hi
Capability matrix sounds the same as what we have at my current workplace, we call it a skills matrix, or sometimes a competency matrix. It has a list of skills required for the job, and at interview the interviewer scores you from say 1-5 on how you match the skills required. Then at the end all your scores are added up and compared against other candidates. Its meant to be a fair way of assessing people. Its used at my work for shortlisting and during interviews. Hope this helps.