I'm probably the single individual who thinks putting Silfverberg in, without practicing, without getting used to NA ice, without getting adjusted to having just travelled 900km and who has never played with the team before is a horrible idea.
But still, Go Sens Go!
Why though? Kid's got all the confidence in the world after his own playoffs, building will be rocking and his adrenaline will be off the charts. Butler and Stone both played give or take 8-9 minutes in game 5, you are telling me that Silfverberg couldn't play 8-9 minutes worst case scenario? You also have to realize that he is a forward, its not like he is a defenseman or goalie, where mistakes are much more likely to be costly. If he's as good as predicted, why not take the chance?
EDIT: Not to mention he plays a two way game, unlike Butler and Stone.