I am a little confused about Double Tackle. Partly this is about mechanics, and partly it's about economy. The mechanics issue is that it doesn't say whose DC you use for the Strength check. Is it yours or your allies? Or the better of the two? The ally moves, and is necessary for the free trip mechanic to proc.
The economy issue is this, it seems like this maneuver costs a ton of points, actions and possibly even survivability for not a lot of payoff. I can see it being situational useful, but most of the time, there's a better way to do this for cheaper. It's an action (as opposed to bonus or reaction) so already your starting off giving up (multiple?) attacks, spells and powerful abilities for 20 ft of free movement to an ally and a trip attempt. Now you can auto succeed on a trip, which is nice, but you have to put yourself AND an ally in a vulnerable position to do so. It also costs 3 points, which is quite a lot. If it uses your DC on the check, there's tons of options in maneuvers that cost you less points or uses a better action economy (or both) to make a free trip attack. It used up your action and their reaction to get 20 ft' of extra move and a trip attack.
I am trying to make a 7th level Marshall that is a swift strategist, which means I can give up one of my 2 attacks to give a free 1/2 move that doesn't provoke AoO to an ally anyways, so the free movement aspect is not really important plus it doesn't cost me my whole action. If I give my ally an attack and they can use a free Sanguine Knot ability with it, they could never use this one because they would need to move 20' first, which they can't do because the movement is given to someone else since they are using the maneuver. Being a reaction (for them) they couldn't make a move action for the 20' needed to get a trip attempt. If the Strength check was made against either DC you could pick a stronger character to do this with, which might be very situationally better, but the odds of it being particularly useful with any regularity is still quite low. This would make a lot more sense if they had to make a check at disadvantage, or hit a higher DC since it takes up 2 people's action economy, but that isn't the case. I am just having a hard time understanding how this is ever preferred over other ways to get extra movement or a trip attempt. Especially with a Marshall/ Fighter that has so many options for maneuvers.
The economy issue is this, it seems like this maneuver costs a ton of points, actions and possibly even survivability for not a lot of payoff. I can see it being situational useful, but most of the time, there's a better way to do this for cheaper. It's an action (as opposed to bonus or reaction) so already your starting off giving up (multiple?) attacks, spells and powerful abilities for 20 ft of free movement to an ally and a trip attempt. Now you can auto succeed on a trip, which is nice, but you have to put yourself AND an ally in a vulnerable position to do so. It also costs 3 points, which is quite a lot. If it uses your DC on the check, there's tons of options in maneuvers that cost you less points or uses a better action economy (or both) to make a free trip attack. It used up your action and their reaction to get 20 ft' of extra move and a trip attack.
I am trying to make a 7th level Marshall that is a swift strategist, which means I can give up one of my 2 attacks to give a free 1/2 move that doesn't provoke AoO to an ally anyways, so the free movement aspect is not really important plus it doesn't cost me my whole action. If I give my ally an attack and they can use a free Sanguine Knot ability with it, they could never use this one because they would need to move 20' first, which they can't do because the movement is given to someone else since they are using the maneuver. Being a reaction (for them) they couldn't make a move action for the 20' needed to get a trip attempt. If the Strength check was made against either DC you could pick a stronger character to do this with, which might be very situationally better, but the odds of it being particularly useful with any regularity is still quite low. This would make a lot more sense if they had to make a check at disadvantage, or hit a higher DC since it takes up 2 people's action economy, but that isn't the case. I am just having a hard time understanding how this is ever preferred over other ways to get extra movement or a trip attempt. Especially with a Marshall/ Fighter that has so many options for maneuvers.
