I've been cogitating on this a couple of days now, and finally decided to try to sort out my thoughts with some data. Berrios just completed his age-23 season. That's a little arbitrary, depending on which part of the year one's birthday falls, but allows me to at least try to define a quick-and-dirty study to avoid cherry picking as much as possible. He started 25 games, pitched 145 innings, and got an above-average ERA+. That's the mark of a pretty good pitcher. Let's turn the clock back 10 years, and find the guys in their age-23 season who pitched at least 100 innings and had an ERA+ better than 90 in the 2007 season. I'm doing this by hand, so I hope I didn't miss someone: Carlos Villanueva - 59 G, 6 GS, 114 IP, ERA+ 113 Brandon McCarthy - 23 G, 22 GS, 101 IP, ERA+ 94 Tim Lincecum - 24G, 24 GS, 146 IP, ERA+ 112 Scott Kazmir - 34 G, 34 GS, 206 IP, ERA+ 130 Cole Hamels - 28 G, 28 GS, 183 IP, ERA+ 135 Zack Greinke - 52 G, 14 GS, 122 IP, ERA+ 124 HOLY MOLEY! That's some tasty pitching to lock up long-term, if you are smart enough to predict the future. I want to eliminate Villanueva from consideration, as his pitching line isn't that similar to Berrios's that year, and he never went on to become a full-time starter. But, if I do that, I miss out on Greinke. I don't think I wanna do that. I want to eliminate McCarthy, as having had a season not up to Berrios's standard set this year. Still, McCarthy has always been one of those guys people talk about trying to acquire, so I assume his reputation was pretty good back in 2007. Being in the majors at age 23 and being given a lot of innings means something. He's broken a lot of hearts since then with tantalizing but injury-riddled seasons, but I don't know how to predict that yet. So I'm gonna say, let's stick with these 6 after all. Lincecum and Kazmir did indeed get lucrative contracts, ones that I believe the signing teams came to regret. They delivered the bulk of their career WAR during their years of team-control. Hamels and Greinke? Yes please. So, suppose you're a GM and by some lucky chance you have these 6 pitchers on your roster at age 23. Ownership is willing to go deep for a few, but not all - and they won't give you a mulligan toward signing someone else to replace any dead money later on. How do you determine which, if any, to buy out of a few years of free agency, and which ones do you go only year to year, knowing only what is known in 2007? Pick the right two, and only those, and you're the next reincarnation of Branch Rickey. Sign too many, and you may be having ownership breathing down your neck. Sign the wrong two, and you're outta there. (Oh, and don't factor in what their actual teams did contract-wise later on, nor whether player and agent would have been open to an early deal, nor that they would have differing amounts of major league service time. Just make the call at age 23, as to whether to open negotiations or not.) I went to b-r.com and brought up the minor league page for each player, combined partial rows, and scrolled so I couldn't see past 2007. One guy went to college and the others were signed younger. Villanueva - steadily increasing workload, no major downtime, reached majors at 22 McCarthy - steadily increasing workload, no major downtime, reached majors at 21 Lincecum - normal-looking college workload, brief minor league at 22, reached majors at 23 Kazmir - normal minor league workload at 18 through 20, reached majors at 20 Hamels - normal at 19, reduced workload 20-21 (injured?), reached majors at 22 Greinke - normal 18-19 workload, reached majors at 20, missed time* at 22, reliever at 23 * For non-physical reasons not relevant to this discussion I dunno. Based on this cursory review of their health, I think I'd reach some wrong conclusions. Back to your assertion about work ethic and exercise regimens, I don't know how to be analytic about it. There's an anecdote about Lincecum swearing off of In-N-Out Burgers, just when things started to go sour for him. He was always known as kind of a flake, so maybe he's the anti-Berrios and does serve as a cautionary tale. But I don't know how outsiders like us can really know who has stellar habits - if you try to infer from their innings workload up to age 23, some of the "wrong" guys above have clean records like Berrios, and some of the "right" guys don't. If I'm a GM, and my analytics team gives me this, I ask them to dig deeper for me. At minimum, repeat this exercise for several more seasons, then see if any refinements to the methodology suggest themselves and proceed with that. I'm certain that this has been done, anyway. So, take this as merely some food for thought. I don't claim to know the last word here. Instead, I'll close with probably the saddest photo I will see all day: