Luck and Fate domains: Good Fortune and Tugging Strands

[Elysiume]

(for reference)
Good Fortune (Ex) (CRB): At 6th level, as an immediate action, you can reroll any one d20 roll that you have just made before the results of the roll are revealed. You must take the result of the reroll, even if it's worse than the original roll. You can use this ability once per day at 6th level, and one additional time per day for every six cleric levels beyond 6th.

Tugging Strands (Su) (APG): At 8th level, you can force a creature within line of sight to reroll any one roll that it has just made before the result of the roll is revealed. The result of the reroll must be taken, even if it is worse than the original roll. You can use this ability once per day at 8th level, and one additional time per day for every 6 levels beyond 8th.

Good Fortune, from the Luck domain, is very clear: as an immediate action, reroll any d20 you've made after you've rolled the die, but before you know the result. Tugging Strands seems much more complicated. It's pretty clear for PC allies: you can see what they've rolled, and let them reroll. Or force, as the case may be. In essence it's a Good Fortune that can be shared with allies.

The question is how it interacts with NPCs, especially enemies. As written, you can't know the outcome of the roll, so there's no option for "the kobold hits" -> "I tug the strands of fate." I'd expect the interaction to need to be more along the lines of "the kobold rolls a 19" -> "I tug the strands of fate," but suddenly you have a player that needs to know every single roll that NPCs make. This would both remove a lot of the secrecy of the rolls and massively slow down any sort of combat or social interaction.

So this leaves 3 main possibilities (I can think of) for how to play this for NPCs, given that the PC ally component is fairly obvious):

The player gets to see every d20 the GM rolls, and can have the GM reroll a d20. Gives a lot of information to the player, and slows down gameplay.
The player knows what rolls the GM is making and can't see the numbers, but may force a reroll once the outcome is known. Gives less information to the player, but arguably stronger--the player doesn't know a random NPCs will save, and thus doesn't know if a raw number would have been successful.
The player can hear/see the GM rolling dice and can randomly tell them to reroll a die. Even if the GM says "and the kobold rolls for attack..." it'd be worthless. Effectively becomes a PC-only ability.

How do people play Tugging Strands? Is there some happy blend of these options (or a particularly good house rule) that works well?

[Geddy2112]

When I DM I roll openly, so I would rule that players get to see the result of the dice and can call for a re roll. They must call for a re roll before I declare the result, and if a player has this ability I would like to know beforehand so I can ensure they can have a chance to see the result and choose to react or not, otherwise I tend to declare the outcome as soon as I know it.

If I was rolling in secret, I would inform the player the number they got on the dice and they would have to choose to make a re roll based on that. This could still inform the player if the check passed or failed (a natural 1 or 20 on a save or attack roll) and clearly the player could infer a low number or high number is a fail or success, but they would not know for sure.
Also, tugging strands can be used a maximum of three times a day, and I would stop informing the player at all if they had run out of uses. I Might not even tell them, but knowing they had the ability allow them to ask. It is unlikely they will be rolling for a mundane joe blow creature attacking or even care, it will usually come up on saves, bluff checks, or any major nova a big baddie is doing.

It falls partly on player responsibility to use this for times they would actually consider doing so, and not just scanning for information and slowing down the game. Or intentionally keeping a single use of the ability open so they can tire kick every secret roll just to figure stuff out. That said, I roll openly as a DM.

[Elysiume]

Hadn't thought about GMs rolling openly; mine have always rolled secretly. That would make this more straightforward, as the cleric can just sit near the DM and peek at the rolls. I don't know if I want to ask my GM to change the way he GMs, though.

The more I think about it, the more it seems like asking for every roll wouldn't be that bad. Or, as you mentioned, only asking for the critical rolls. It'd get pretty tiring watching all of the strands of fate, waiting for one to tug, rather than just keeping an eye on the crucial threads.

[Geddy2112]

A lot of great GM's I have had roll secretly, and if you are in this situation explain this domain power to them, and how they can meet you halfway without having to fundamentally change their DM style. At worst, it becomes a power to help your character and the rest of the party, which is still very good.

This power comes online at level 8. Nobody using this power cares what some summoned bear rolled to attack them. Your standard joe blow NPC or less than CR equal opponent is a joke. You can generally tell if shopkeeper #37 is lying, and you can easily discern things that are actual threats to you. Plus you are very likely to use the power to save yourself or a party member from an unfortunate natural 1 on a save. Basically, you know when you need to keep your finger on the pulse and in those nailbiters you will be doing so.

[Elysiume]

I'll talk to him about it, and see what he thinks. He may just want to keep the complexity down (he's a relatively new GM and several people in the gym are brand new to P&P RPGs in general), or he may be willing to do a middle variant of Tugging Strands. Thanks for the input!