Having recently been on the receiving end from an un-errata'd adventure, I understand why.

Taking 37 Stamina (*without* any die exploding) completely breaks the combat system.

+2 speed +3 recovery for a d6 (average +3.5) additional damage is sub-optimal in my opinion. Even at Passive Arcanum of 30 it is still only +2 speed +6 recovery for a d12 (average 6.5) damage. If you are playing a divine caster with no maneuver yet a high Melee Skill, I can see the effectiveness, otherwise that extra recovery is slowing you down too much (not counting fate point pops).

Eh, you can ignore my question. I found what I was looking at and they don't attack. Thanks for the answers!

Stack not attack right? What two things were you talking about?

...snip...
It is one maneuver. No stacking issue. It deals both static damage bonuses. Stacking never comes into play, because there is only one source of damage the advanced maneuver Powerful Might Thrust (are whatever you want to name it).

The same as if you combined two damage spells into one Advanced Spell. It deals both halves of the damage (defenses pending) no stacking issue.

Example of an Advanced Maneuver
Mighty Swing + Sweeping Strike
Category: Advanced
Attack: Avoidance (Prowess)
Speed (Recovery): +2 (4)
Range: Melee
Effect: Weapon +5 damage. You may perform an attack against any two opponents within melee reach; each attack must be rolled independently. You may attack an additional opponent within range once you reach +6 with any Melee skill specialization.

Page: 256 (Errata)
Under Example of an Advanced Maneuver change the
Maneuver's speed to Speed (Recover): +1 (5)
Under Category, speed & recovery change the first
paragraph as follows:
Speed & Recovery: Use the slowest maneuver’s Speed cost and apply the faster maneuver’s Speed or Recovery, whichever is higher, as additional Recovery.
add the following sentence to the end of the Effects entry: When creating an advanced martial maneuver that grants multiple attribute dice, only one die may explode. Also you may not combine maneuvers with a Push speed.

Powerful Thrust + Mighty Swing
You wreck your opponent.
Requirements: Athletics 3 and Melee (Balanced) 3
Category: Advanced
Attack: Avoidance (Pr)
Speed (Recovery): +1 (4)
Range: Melee (1 Target)
Effect: Weapon +5 +Passive Might; you must move 5’ toward your target before performing this attack.

Vital Strike + Devastating Blow
Requirements: Melee (any) +12
Category: Advanced
Attack: Avoidance (Mi)
Speed (Recovery): +2 (2)
Range: Melee
Effect: Weapon; you deal an additional (Mi) die of damage and you deal an additional weapon damage die, suffering a -4 penalty to your Avoidance until your next action. For examples, if you are using a weapon that deals 1d8 (Mi) on damage, roll 2d8 (Mi) (Mi) instead; or if you are using a weapon that deals 1d6 (Qu) on damage, roll 2d6 (Qu) (Mi) instead.

@Eric: Hmm... I've never seen anyone think they would get weapon (including attribute) x2 for an advanced maneuver. But I guess you are right, it doesn't say you only apply weapon once, although the example proves that and the errata talks about none+weapon.

My point is the following maneuver would look like this:



You would get the +5 damage and the +Passive Might damage. Although they are both static bonuses to damage Powery Mightful Strike is one maneuver. When you declare you are using them together as an advanced manevuer, it is one source of bonuses.