Super Two players go to arbitration four times instead of the normal three. Every year, a group of players with more than two but less than three years of service time gets to go to arbitration for the first time and score millions, while many of their peers who miss the cutoff are still earning less than $500K. The salaries build upon themselves, so it's not just a single season affected.
The cutoff varies year to year - last year Brad Ziegler was a Super Two with two years and 122 days, but typically it's over 130 days. CAA indicated in April that it could be 146 days for 2012. It is determined by calculating the top 17% in total service of those with two to three years, assuming the players had at least 86 days in the previous season. Usually if a team promotes a player in June or later he will not achieve Super Two status.
This has led to the cynical opinion of many observers that any decent prospect who makes his MLB debut in June or later is a victim of the Super Two numbers game. That's not fair to teams, as there are often good developmental reasons to give a prospect more seasoning that might not show up in the box scores. For example, Dave Cameron of FanGraphs demonstrates that the Mariners don't have Dustin Ackley in the minors because of Super Two. And as Blue Jays GM Alex Anthopoulos pointed out, most players are optioned at least once, changing the equation. The problem is that we can only guess as to each team's motivations.
Kevin Goldstein of Baseball Prospectus discusses the Super Two situation today, noting five players who could start next season in the minors for financial reasons. He says that while "players and teams alike aren't especially fond of the system," giving it up entirely would be a major concession for the players' union. An NL exec pointed out to Goldstein that you can't really eliminate the ability of teams to make service-time based decisions just by cutting out Super Two. The same concerns would just arise in April, as teams would be accused of trying to keep a player just under a full year's service time to delay arbitration. Of course, those concerns already exist in April as teams sometimes try to delay free agency by a year.
So there is something to be gained for teams and fans by eliminating Super Two, as service time debates would be limited to April. The players would need some kind of concession to give up Super Two, as every year 15-20 of them earn extra hundreds of thousands or millions because of it (even if many are later non-tendered or signed to extensions). I wonder whether the players would be open to a new proposal that benefits all young players, rather than just a small subset with the appropriate amount of service time. For example, what if the minimum salary is raised a bit more than usual to compensate for the loss of Super Two? Another possibility would be to drop the 17% qualifier to, say, 10%, creating fewer Super Two players by effectively pushing back the cutoff date. Let's hear your ideas in the comments.