Parting with key men is never easy, particularly midway through a season.
Rovers, though, were prepared to let club captain Dann step back up into the Premier League when Palace came calling at the end of the winter window.
The Ewood Park outfit need to cut costs and moving a top earner out, while bringing in a fee which could rise if certain clauses at met, represents good business for all concerned.
Managing director Derek Shaw told the Lancashire Telegraph: "We were not happy to lose Scott but it's been well documented that he was a Premiership-earning player and we had to try and cut that back.
"We've got some cash up front, we will receive further payments if Palace stay up, and if Palace do not stay up we are covered if they go back to the Premier League with payments. We also have payments over games.
"We are as happy as we can be with what we've got for Scott. With the sale and the money coming in, we are heading in the right direction."
Rovers were also able to add in January, as they brought in Tom Cairney, Rudy Gestede and Craig Conway, and Shaw considers the winter window to have been a success.
He added: "I think we've had a pretty successful window.
"Two or three of the overseas players have left permanently, a number of young players have gone out to get experience elsewhere, while there's one or two who have gone out on loan who at this stage will come back after their loans unless offers are received. But they are good savings on our books.
"At the same time, we've managed to bring in a pretty exciting signing in Tom. Everyone wanted us to do it so it was terrific news that we got it done.
"We also brought in Rudy, who seems to be getting better with every game and becoming a popular player among the supporters, as well as Craig, who was in big demand but who set his sights on coming to Rovers."