It's really hard to separate the effects of each of these nutrients, because they have to be interpreted in the context of each population. You're referring to The Lancet paper that I think was published in the summer. This was a multi-country study, and the context of carb consumption is very different among these countries, so we have to be careful how we interpret the data.
For example, the Mediterranean diet is not a low-fat diet, but it's a healthy fat diet. According to that paradigm, we could shift towards a higher fat diet if you consume the higher quality types of fat. However, the risk with the higher fat diet is to accept the higher saturated fat diet from transformed products, which are not to be recommended. You have the Atkins diet that has been promoted quite a lot. This is a high saturated fat diet that had some effect on cholesterol, but we don't have any long-term study to support that.
I don't think we need a recommendation on the amount of carbohydrates we should consume. This is variable from country to country, from population to population, even within Canada, but I think if you consume the right types of fat, then it's okay to consume a higher fat diet.