Right. It is a resource use issue. And no, an Urgosh's higher damage die does not make up for -1 to hit. Would you take Power Attack it if were -1 to attack for +1 damage? I can't see that as a good benefit for *anyone*.
The loss of the Offhand keyword is what stings more than the other nerfs. The issue where all ends of the weapon counted for all keywords was clearly not working. Dropping the damage die on the spear end of the urgosh and the main end of the sword was fine. The loss of the Offhand keyword hurts for tempest fighters.
That being said, the build of tempest fighter seems to emphasize the mobile skirmisher more than the junior Two Weapon Ranger. The nerfs to Double Weapons make the choices available more indicative of that aspect. With Dex as a recommended Secondary, the Double Sword is an easy choice to make, same with the Spiked Chain. Of course, that and the Staff are on the chopping block, so who knows what the story will be once they are examined.
Jay