CPLZ,
My opinion is that House's recommendation seems to make sense more for players who are pitchers only. I do believe players should throw frequently and long toss is part of that. For players who are pitchers only, they might as well do all of that throwing in a way that reinforces their pitching. But, for other players, I don't feel this is absolutely necessary.
Now, on the travel team I coach, we try to use as many of the players as pitchers as possible so that we don't abuse arms in the pitching marathons otherwise known as travel ball tournaments. So, when I conduct a pitching practice, I instruct the players to use proper pitching mechanics and to throw only from a distance where they can maintain proper mechanics. At other practices, I let them air it out like outfielders.