I suppose in some sense it flows but watching the World Cup I notice that there are constant little stoppages of play -- the ref is always blowing the whistle w

I suppose in some sense it flows but watching the World Cup I notice that there are constant little stoppages of play -- the ref is always blowing the whistle when two players collide going for a ball, any time there is a challenge (and an opportunity to mug and dive and generally lose dignity ;) Restarts happen quickly to be sure but the whistle stoppage seems to take some of the momentum out of the game. It would be better if the refs just let the players play and only blow the whistle for the most egregious fouls.