The Cambridge Law Test does not account for a large section of the admissions process at Cambridge. As none of the cohorts which have taken the CLT have graduated yet, the Faculty has not had the chance to correlate the scores in the CLT and the final degree classification. Therefore, whilst it gives them an indication of a student's aptitude for Law, it is by no means make or break.
This is what I got told when I asked about the significance of the CLT at my interview.