The purpose of bursting that pack and letting it swell is just to tell you that there's live yeast in the pack. Not going through that process won't hurt anything.
What you should do to improve things, though, is to make a starter with that yeast pack. That kills two birds - it tells you that the yeast is alive AND it get your cell counts up to what they should be for pitching. While Wyeast claims that the pack is directly pitchable, in general, if you do the calculations, there's nowhere near enough cells.