I'd really place the SW as above the SI in just about every regard. The SW is the one who manipulates and plots while the the SI is the one who just blows stuff up.
One is a slim dagger placed precisely between the ribs of a target or a sharp scalpel surgically manipulating events from a distance. The other is a hammer and has the subtlety of 2 kilos of solid iron at the end of a long piece of wood.
Yeah kind of a shame that the SI is the 2 kilos of solid iron though.