Obviously one of the bigger issues in baseball right now (at least among us prospect geeks and transactional nerds) is the concerted effort by teams to manipulate the service time of their top prospects in an effort to squeeze out additional time on the roster. For those unfamiliar with the situation, that effectively means keeping guys in the minors a few extra days into the season to prevent them from become free agents for in practice seven years, or keeping them in the minors a few extra months to prevent them from becoming Super 2 players.
The union is unhappy about this, and in thinking about it recently, I have what seems to me an interesting solution: major league service time for minor leaguers.
That's a bit crazy, so let me explain what would happen. Every day, take the top 10% or so league and park-adjusted statistics (effectively wRC+), and the players who appears on that list are credited with a day of major league service. This would include all levels of the minors, and take into account level differences, normalizing them to AAA. This means that a player who is in the top 10% in the CAL, after level adjustment, might not be in the top 10% overall. But a player who is in the top 1% could be.
Salary could also become an issue, but there's a simple fix to this. "Service time" would effectively be split into two groups: MLB service, and Credited service. Both count the same when it comes to determining arbitration eligibility and free agency. Only MLB service applies to things like minimum salaries in the minors - this means that a long-term minor league vet would not be making millions to play in AAA; you can pay the veterans the same amount you always have, because they only have Credited service.
This achieves three things. First, it encourages teams to promote their prospects not only to the majors, but to their appropriate level. I don't think this is a big issue to begin with, but if a guy is destroying the Sally league and as a result is accruing service, the team might deign to bring him up to High-A in order to bring his numbers down a bit and stop the clock from ticking. If he's having that good a season, he should probably be moved up anyway.
Second, it presumably fixes the service time manipulation issue. Gregory Polanco would be in the majors right now - he has a 202 wRC+ in AAA, and with this rule there would be no reason to keep him down. Oscar Taveras would probably be up. George Springer would have come up faster.
Third, it prevents teams from sitting on gaggles of prospects in the minors. This is basically just a more extreme version of the Rule 5 draft, where it would take a considerable time for a team to actually lose a player, but encourages the club to maximize the amount of talent it has at the major league level. Reducing the value of prospects would likely encourage trades, as well as ensure that teams are more willing to win now.
I'm sure there are ways for teams to get around this, as well as problems that would arise. I'm interested to hear thoughts on the subject, including possible alternate solutions, because I imagine this will be a major bone of contention for the next CBA.