It's not like the 60 minute Sacrifice makes us not want to use our pets even more. I mean Sacrifice is apparently the top talent for Affliction anyway.
THAT'S the incentive to use Sacrifice.
If you're going for Sacrifice you want to keep it up all the time - having a pet out at all with Sacrifice would just be a DPS loss.
This just makes it so I don't have to keep summoning my pet every 20 minutes just to sacrifice it again.
It's a convenience buff, not an incentive buff.