This paper tackles the current sharing problem for interconnected power converters. Specifically, it considers a single load, fed by buck converters via a common DC bus. In such a case, it has been recently shown that dynamics related to (i) voltage regulation and (ii) current distribution can be completely separated without resorting to frequency separation argument, which inevitably lowers achievable performance. In this paper, the origin of this separation is investigated. A comprehensive analysis is provided by relying on geometric techniques. Controller design example exploiting the new structure is also proposed. Numerical simulations promote the decomposition benefit and illustrate the geometric notions.