There's a chance that Pearce has chalk for bones, but he has averaged 20 games a season for the past three years, is an AA-calibre tall defender, is loved by the playing group who named him Captain, is loyal to the club, and has a chance to be the selfless wise old head when Brayshaw and/or Serong are leading the team at a relatively young age.
I understand why a one-year contract is a more pragmatic step for the list, but it's not how to run a footy club, and there are probably 10 other clubs who would gladly offer Pearce a three-year contract.