This is a question about rhetoric, not the Tory health policy, but I am using that as an example of the technique in question. What I want to know is the name of the technique.

The example concerns the Tory's frequent proclamation that the key feature of the NHS is that it is free at the poinht of use. But that's only part of it: with the right package, any private health insurance is also free at the point of use - after all, that's the basic concept of insurance in the first place. No, the key feature is that it is free at the point of use AND universal AND charges via tax are not dependent on what treatment you have received earlier.

So in short, the rhetorical technique is to emphasise one true feature of something, over and over again, and so implicitly downplay the other factors that are also important. It must have a name ... but what is it?