I believe stevef describes it nicely.
I think having a full understanding of the areas of risk in the inspection of, for example, a control surface cable routing such as stevef mentions is better than following a check list which has a certain 'ticking boxes' element to it. After all, becoming an LAE is a very lengthy process and you build up a good understanding of the full picture of what can go wrong during maintenance procedures. You are also very aware that your licence is on the line if you miss something and that focuses the mind wonderfully. Where things could go wrong is where the duplicate inspection was not assiduously carried out and I have known it happen - maybe things are better now. No one is perfect and I wanted the duplicate carried out as if it was the initial, not just a rubber stamp of that. I suppose it's similar to having a suitably assertive PNF who is not afraid to challenge the PF's decisions when appropriate.