Nah, that's BS. It's an argument from authority, there is no actual science done in that paper.
Now if they actually took people, and replaced saturated fat in their diet with polyunsaturated fat, holding other variables constant, then measured whether they lived longer, they'd have something. But they haven't done that.
Their reasoning is that this measure of blood lipids is associated with CVD, so if we do something that lowers that measure of blood lipids, it will also lower the incidence of CVD. That's just bad science, and they should know better.
Now if they actually took people, and replaced saturated fat in their diet with polyunsaturated fat, holding other variables constant, then measured whether they lived longer, they'd have something. But they haven't done that.
Their reasoning is that this measure of blood lipids is associated with CVD, so if we do something that lowers that measure of blood lipids, it will also lower the incidence of CVD. That's just bad science, and they should know better.