On the other hand the Sox are paying $70 million plus for Rusney Castillo to entertain the PawSox fans, even though there's no tax hit.
When you've got that much money invested in something, you will want to recoup whatever value it has if possible.
It's very confusing stuff. There are also some penalties that apply if you exceed tax thresholds AND sign a free agent who received a Qualifying Offer.
And a lot of that is the elusive nature of the game.
But there are no numbers to support the idea that Kelly is a huge loss for the pen.
He was great in the playoffs, absolutely. OTOH Kimbrel was terrible in the playoffs.