Even so, the "loose everywhere but the boots" look ends up making one look fat. Loose ends up eliminating the person's shape and substituting the garment's shape. Unless the garment has a very purposeful shape, then it just results in making the person look large and shapeless. In this case, it's apparently not so much of a concern due to the necessity of the situation (layering with a sweater). One should always envision a shape one is trying to achieve and choose wardrobe according to the achievement of that shape. This is, of course, a slightly idealized vision of fashion, since not all of us can achieve the shape that we'd like to achieve, and as such the goal should be achieving the best shape possible at all points in time. Now, this shape can change depending on occasion, but there are certainly shapes that make us look better, and shapes that make us look worse (if I wear tapered trousers, I end up looking slightly ridiculous, because my natural body shape does not support this sort of thing).