The cannith crafting tooltips on the twilight shards are wrong. I submitted a bug report but I'd like to tell anyone that's interested. The 10% arcane failure reduction shard for only adds 1 minimum level if the armor has a minimum level and the 20% arcane spell failure greater twilight shard only bumps the minimum level by 4 and I'm guessing 3 if the item has no min level.
Before the shards read 2-3 levels and 9-10 levels.
While this is very helpful it would be nice if the tool tips could reflect actual penalties so these armor don't look so out of reach. My melee sorc will be upgrading his twilight leather to twilight scale mail very shortly .