All valid points, scratchbomb. Should they sign Pedro, their rotation would consist of (probably not in the correct order):
Hamels
Happ
Moyer
Blanton
Pedro
That's not a bad rotation. However, if they add Roy Halladay, this becomes a great rotation. In the post-season, a 1-2 of Hamels and Halladay would be nearly unbeatable. Moreover, the Phillies have a deep enough farm system whereby they could afford to trade for Halladay without killing their depth. If the cost is too much, which it may very well be for the Phillies, then Amaro should walk away. But I think the Phillies at least need to consider a trade for Halladay.