Here is my theory, You can buy weathered gear with solidarity tomes it is ilvl 100, however you can get one of the following drops in new coil.

Sands of Time - Born of Allagan ingenuity, this peculiar sand is said to possess the power to turn back time.
Oil of Time - Born of Allagan ingenuity, this peculiar oil is said to possess the power to turn back time.

Once you use one of these items it restores the item and makes it 110. Kinda similar to the system they had in wow in where you could buy tier gear with valor points but if you wanted to upgrade it to max item level then you would need to do the heroic raid to get the token and trade it in with the base piece. That's what I am speculating anyway. If they did this it takes some of the RNG out of gearing up. But I am guessing bosses may not drop these time items that often, and every one in the group will want them to upgrade their gear.