One minor leaguer who pays off, and gives you 6 years of below market performance pays for a lot of busts.

Porcello may never pitch in a major league game.  That's a real possibility that you have to consider based on history.

I've written diaries before on the less than pleasant results that usually come from drafting a high school pitcher in the first round (under a third will ever make the majors, and only around 13% will ever be considered good major league pitchers).  So if you want to know why I consider it a risk you can look those up (sorry, but it would be way too long to writeup as a comment).  The Hardball Times has also done a few really good analyses of the risks of drafting high school pitchers.  You should check them out if you get a chance.

I will make this comparison.  Since most of us would agree that Porcello is the best high school pitcher in the draft, let's look at high school pitchers that were taken first in the draft for a comparison.  The #1 high school pitchers are usually drafted in the top five picks in their respective drafts, with only J.M. Gold (1998) not being taken in the top 10.  That should be a relatively fair comparison, right?

Of the #1 high school pitchers taken in the drafts from 1990-2004:

1.  Only seven (of the 15) have ever pitched an inning in the major leagues.
   
2.  Only five broke the 100 IP barrier.
   
3.  Only Josh Beckett, Kerry Wood, and maybe John Danks someday will ever be considered above average pitchers.

So would I rather sign a league average pitcher (Padilla has a career 101 ERA+) to a 3 year - 30 million contract than take a risk on Porcello?  Probably, since 10 million's probably going to be about the going rate for a #3-4 starter after this offseason.  But that's me and I almost always value actual production over potential.  Others think differently and both approaches have been shown to work at the major league level.

I agree SF is a scary problem, but TB, Cincy and Pitt don't really scare me.