In a comment under this fanshot, somebody asked who on the current roster has been to the Arizona Fall League. I thought this was an interesting question and did some research. All you have to do to find out is take the current 40-man and compare it to the list of Arizona Fall League alums here (A-K) and here (L-Z).
It turns out there are 17 current Tigers who played in the Arizona Fall League at some point and 25 who didn't. I decided it might be fun to make a roster of each to see how they compare, and at the same time learn a bit about who sees the Arizona Fall League and who doesn't.
AFL Roster
Pitchers
Doug Fister SP (Mariners 2008)
Max Scherzer SP (Diamondbacks 2007 and 2008)
Brad Penny SP (Marlins 1999)
Andrew Oliver SP (Tigers 2009)
Brad Thomas RP (Twins 2002)
Luis Marte RP (Tigers 2008)
David Pauley RP (Red Sox 2006)
Joaquin Benoit CL (Rangers 2000)
Position Players
Don Kelly C (Tigers 2003 and 2005)
Danny Worth 1B (Tigers 2011)
Will Rhymes 2B (Tigers 2008 and 2011)
Brandon Inge 3B (Tigers 2000)
Cale Iorg SS (Tigers 2009 and 2010)
Delmon Young LF (Devil Rays 2003 and 2004)
Austin Jackson CF (Yankees 2008)
Ryan Raburn RF (Tigers 2004)
Jhonny Peralta DH (Indians 2002)
As you'd expect, the roster is a little lacking since it only has 17 players. We barely had enough to fill out the lineup and had to get creative to field a catcher and a full infield. This team's rotation does boast 3/5ths of the Tigers' rotation, so that could be considered a strong suit. That bullpen, however, would make for a lot of fingernails chewed to the quick as they tried to bridge the innings until Benoit took over.
As a whole, though, it seems like this roster lacks a lot of the real Tigers' star power. This squad is mostly comprised of role players, average major leaguers and sometime All Stars. So let's see if we can get a feel for the type of players who get sent to the Arizona Fall League.
Despite what I'd consider a lack of MLB stars in the Tigers' AFL vets, the league does see its share of top prospects. Of the Tigers' alumni, this includes Max Scherzer, Brad Penny, Austin Jackson and Delmon Young. The funny thing about this list is none of these players were assigned to the AFL as Tigers. If you wanted to add a Tiger to the list, you could probably add Andrew Oliver if you relax the terms of "top prospect" a bit. His assignment to the AFL was his first taste of pro ball after getting first round bonus money in the draft and sitting out the minor league season as an August 15th signing.
I'd say another category of AFL assignees are players who are rapidly rising and the advanced league is used to measure how ready they are for the next step. Falling in this group at the times they were assigned would be Luis Marte, Brandon Inge, Ryan Raburn and Jhonny Peralta. Marte qualifies in a second group the Tigers like to send to the AFL. That's pitchers who are decent prospects and had their season cut short by injury. The Tigers seems to like to use the league to have these pitchers catch up on lost time.
Next you'd seem to have players who might be stagnating a little bit after reaching Double A or Triple A. In this instance, teams probably just want to get more of a look to determine whether they're stagnating because they are hitting their ceiling or they just need more work to break through. I'd put Doug Fister and Cale Iorg in this group. Fister was sent to the AFL after his second unimpressive season in Double A. The first time Iorg was sent was after an unimpressive turn in Double A.
The final grouping would seem to be players who are destined to be fringe major leaguers. They may have shown promise as minor leaguers, but their eventual role in the majors (if they make it) is unlikely to be as a starter or regular. These guys are likely sent to fill out the AFL rosters so the teams have enough players to cover the necessary innings. With some exceptions, players who go to the AFL twice likely fit into this category. I'd say this group includes Brad Thomas, David Pauley, Don Kelly, Danny Worth, Will Rhymes.
Non-AFL Roster
Pitchers
Justin Verlander SP
Rick Porcello SP
Jacob Turner SP
Brayan Villarreal SP
Adam Wilk SP
Duane Below RP
Jose Ortega RP
Phil Coke RP
Ryan Perry RP
Daniel Schlereth RP
Joel Zumaya RP
Al Alburquerque RP
Jose Valverde CL
Position Players
Alex Avila C
Miguel Cabrera 1B
Carlos Guillen 2B
Wilson Betemit 3B
Ramon Santiago SS
Brennan Boesch LF
Andy Dirks CF
Magglio Ordonez RF
Victor Martinez DH
Omir Santos C
Ryan Strieby 1B/DH/Emergency OF
Clete Thomas OF
This team actually looks a lot more like an MLB team, even if their starting rotation is a bit thin. It has the Tigers' superstars and because it has more players, fills out the squad more easily. One thing you'll notice is the reason some of the highly touted players don't make the AFL is because they rose through the minors too quickly. Guys like Verlander, Avila, Martinez and Cabrera were already in the majors by the time most players would enter the Arizona Fall League roster conversation.
The rest of the players spent offseasons where they might have been eligible playing in other leagues or just never had the stars align right. Foreign players can only be assigned to the AFL if they aren't protected by their home country's winter leagues. Other guys may have lost their chance due to injury. Strieby may have seemed like a perfect candidate these past couple years (he's been selected, in fact) but his wrist injuries have kept him from going. As for pitchers, the explanation could just be as simple as them not needing the innings.
One thing is for certain. You do not gain much of an idea about a player's future from whether he's selected for the Arizona Fall League. You have to dig down into his specific situation to get an idea for why he's going and even then there are no certainties. I think as the league has gained more notice, we've tried to read more into assignments than we should. We also tend to make too much of how players do once they are there. We need to realize it's just another chance to look at players and another chance for players to build the body of work we use to get a feel for their futures as big leaguers or minor league veterans.