I wouldn't be surprised if the Swans have been trying to work on something to prise pick 12 or 13 from GWS, especially after they indicated a week or so ago that they were willing to part with some draft picks to get more experienced players into their squad. Unfortunately, I am not sure that either TDL or White would be what they are looking for. They'd be after players - not necessarily stars but solid performers - in the 24-26 age range, something the Swans don't have an abundance of and those they do have (Kennedy, Jack, Smith) are players they'd been least likely to part with. Bird is the only one in this age range who I think they might consider trading.
Of course, Crows fans would argue pick 12 or 13 is still not enough, given many of them have their hearts set on a top 10 pick and another in the 10-20 range. But the closest similar trade of recent years to the Tippett trade was Mitch Clark (similar age, out of contract, big contract offered, attractive more for potential and flashes of brilliance than sustained, top quality performance) who was traded for pick 12, IIRC.