Preface - This is PURE speculation. It's not *completely* baseless, but what basis exists is purely circumstantial. I have never let that stop me before and I won't now. I'm not a journalist - I'm a Supporter!
The first thing that had me wondering if a rule-bending, rule-change or team-specific accommodation might be coming is the Matias Laba situation at Toronto FC. Laba is an excellent young midfielder and was one of the few truly bright spots for the Reds in 2013. Toronto signed him as a youth DP and are reported to have paid a $1.5M transfer fee to acquire him. In addition, Laba was making $200K in salary at the last reveal in September. With that transfer fee spread over three years, his natural (non-DP) cap hit would be $700,000. Since the season ended, Toronto FC has gone on to make a HUGE splash in the offseason signing Michael Bradley, Jermaine Defoe and Gilberto - each to multi-million dollar contracts. That leaves them with 4 DPs. There has been a lot of speculation about a loan for Laba with teams like Toluca reported to be interested. Toronto, however, really really really wants to keep Laba. Training camp has started and Laba is there with the team (along with the other 3 DPs). There are no indications whatsoever that he's being moved - and trust me, I've been looking (I really like this kid). Why wouldn't Toronto be publicly and actively shopping him?
Now we have #DrogbaWatch - Silly season is back in session. Speculation abounds that Chelsea legend Didier Drogba will be making a move to MLS this summer. At first it seemed to be a silly rumor. Now, however, the original source claims HIS source is the manager at Galatasary. People who don't normally delve into the messy world of transfer rumors have piped in on this one. Adrian Hanauer said "it's a rumor" - in AH-speak that reads as a non-denial denial. Then there was the photo with Gary Payton...and Jeremiah Oshan thinking he saw Drogba at the airport. In fact, there is enough momentum behind this that I would normally be inclined to buy in. However, moving a proven, world-class and much younger DP like Oba to bring in Drogba midseason just didn't seem to fit the offseason narrative our Front Office has been spinning. However, bringing in Drogba *in addition* to Oba...that feels more in tune. It may not be a position of extreme need for the Sounders, but Didier Drogba is a player an MLS team does not pass on when given the opportunity.
Timing - MLS is an opportunistic league and single-entity allows for a degree of agility that could make this sort of change possible. The opportunity comes with the World Cup in Brazil. Players are famously more willing to make moves after the Cup than they would have been before. In addition, many teams will be here in the US playing pre-Cup friendlies. Garber may simply see this as an opportunity to grow the league.
Timing again - The CBA negotiations are right around the corner and there is very little doubt that, with a new and improved TV deal, the players will demand a significant loosening of the salary cap. An additional DP could easily be a facet of that loosening.
Lastly, there is plenty of precendent for the MLS making significant rule changes like this, notifying the clubs, but not publicly announcing the change. Most recently, there was the 2012 tiebreaker rule change (which was made at the beginning of the season, but not announced until mid-season) and the CCL Berth change that sent Portland into international play while RSL is on the outside looking in (the change was recommended at the start of the 2013 season). Just because we haven't been told of a rule change clearly doesn't mean one hasn't been made.
So I wonder aloud, is a 4th DP coming? I don't know. It would not surprise me. We'll find out, one way or another, when Donnie G and company decides we need to know. Not a second before.