What is the difference between the flour batter and sugar batter methods for mixing a cake?

In the flout batter method, the flour is added as two separate portions, firstly mixed with the creamed ingredients with a second portion added later to the batter. The flour and fat are mixed together, while the eggs and sugar are whisked together in a separate bowl. The fat is usually creamed with a similar about of flour, for example: 400g flour to 450g fat to obtain a suitable creamy mixture. Once the eggs and sugar are sufficiently whisked to form a foam they are added in small portions to the flour and fat mix. Once these two portions are combined together in a cohesive batter any additional flour is added.
The sugar batter is based on the emulsion of oil in water with air bubbles being trapped in the fat phase while other ingredients are dissolved in the water phase. The fat and sugar are creamed dependent on the temperature and creaming quality of the fat to produce a light mix. The liquid egg is added in 4-5 portions with creaming in between each addition to prevent any curdling occurring and producing a batter that is smooth and has a velvety appearance and texture. Sifted flour and any additional water or milk are then gently added to the batter.