I wanted to provide an update to this topic:
With the ZG enchantments coming out, we noticed that a few of those enchantments suffered from a similar bug to the one preventing Devilsaur Armor from granting +2% hit (which we fixed in September). In particular, the Zandalar Signet of Might wasn’t granting its +30 attack power when applied to the Highlander’s Leather Shoulders, which also have +30 attack power. We have a fix ready to deploy with next week’s maintenance to make these enchantments provide the value they were intended to, even when applied to items with the same effect built in.
We also noticed that our first round of enchantment fixes to prevent enchantments from consuming buff slots missed some of the enchantments that could be flagged to avoid consuming buff slots. The powerful ZG enchants, and “Arcanum” enchants are among these, and we also have a hotfix to keep these from consuming buff slots, which will also be out by next week’s maintenance.
There may be some enchantments whose effects are complex enough that they can’t be marked passive, but we’ll do our best to mark any passive that can be, so they won’t consume a helpful buff slot.
We hope this helps players who stack buffs and recently discovered that their ZG enchant was pushing off a buff. We’ve seen that some players enjoy buff stacking, and we don’t want the ZG enchants to be a power-loss trap that you can’t fix without replacing the gear.