To be honest it also depends on british or american english, n even for the word sword, the w is not exactly silent, but pronouncing the W too prominent is also incorrect; pronouncing it sord is also wrong, the w actually hav the same effect like the e behind hatE, it determines how long or short the letter sounds. Cos if its spelled sord u will be pronouncing it as sot instead. Hence the w is somehwat exists just its not a very emphasized W. The w is just the mouthing after u pronounse S, not the full sound.