True, but proving the absence of side-channel attacks is not currently feasible (it's a very active research area, though - feel free to ask if you want to know

True, but proving the absence of side-channel attacks is not currently feasible (it's a very active research area, though - feel free to ask if you want to know something). And tptacek has a point: sadly, most devices break well before side-channel attacks are worth considering.