Speculation is sure to abound about Collier perhaps being forced to go back to his old role or that he couldn't deal with the added responsibilities, but the real reason behind the move might never come out.
But the bottom line is the move was made, and exactly why isn't the most important question of the day.
The other question is a lot more significant because it will have a long-lasting effect on the Dolphins.
First off, we can tell you Coach Dave Wannstedt said Collier will not return to the role of offensive coordinator, that Foerster will be the offensive coordinator, plain and simple.
Wannstedt sang the praises of Foerster, referring to compliments Foerster received from players and coaches we had worked with, from Ravens head coach Brian Billick, to Colts head coach Tony Dungy, to Colts quarterback Peyton Manning.
But the bottom line remains that Foerster has never been an offensive coordinator in his 12 years of coaching in the NFL.
In itself, that might not be such a big thing, but the Dolphins have two guys on the staff who have been offensive coordinators before in Jerry Sullivan and Marc Trestman.
With improvement in the offense being so critical to the Dolphins' success in 2004, and with the 2004 season being so important for Wannstedt's job security, one obviously has to wonder why he didn't go with either Sullivan or Trestman instead of trusting the offense to a first-time coordinator.
Sure, Collier was going to be a first-time coordinator as well, but he has been with the team for a while, so picking him over Sullivan or Trestman earlier this offseason made sense from the standpoint of continuity.
That doesn't apply with Foerster.
Wannstedt said during the press conference there were two reasons he selected Foerster to replace Collier — he wanted to maintain continuity and the balance between run and pass; and he didn't want to disrupt the quarterback and wide receivers positions by pulling Trestman or Sullivan away from those spots.
Yet another factor, and something Wannstedt never would say publicly, is that he's more certain the offense will run the way he wants it to if Foerster is the coordinator than if it's either Sullivan or Trestman.
As a first-time coordinator, Foerster isn't as likely to want to force-feed his ideas as Sullivan or Trestman.
That might be important to note because Wannstedt is a defense-minded coach whose offensive philosophy is controlling the ball and minimizing mistakes. That's not necessarily the thinking of either Trestman or Sullivan, both of whom would be considered more pass-happy coaches.
Let's be honest, Wannstedt does not want to have a wide-open passing attack, and he might be thinking it will be easier to have the offense run his way with a first-time offensive coordinator who is not as likely to push his own ideas because of a lack of experience or because there's a gratefulness factor.
Regardless, the Dolphins offense will look very similar, despite new players and coaches, as long as Wannstedt is the head coach. It doesn't really matter if it's Joel Collier or Chris Foerster.
It's actually really Dave Wannstedt's offense.