You're still wrong regardless of which board you post at.
The only situation we're talking about is Voidwatch, because using that piece of shit otherwise is retarded.
You start the fight with 300TP, activate AM3. This whole doing Sekka>Darkness thing is folly because it only applies to situations where using that weapon is retarded. You aren't doing that in VW.
Devaluing melee rounds, great, again it only applies in situations outside Voidwatch where again, you shouldn't be using that weapon.
In VW, you've got LR/DB up the entire fight, with 2x Marches or Embrava. If you can manage to never overTP, great we luv it. Otherwise, in the real portion of the game, the number of melee rounds required may be 3~4, but the number of melee rounds that occur is almost assuredly 4~6.
You're talking about doing less than 1000dmg difference on a WS (Quietus) to activate a 50% ODD rate for 90s. You make that damage up within the first 10s of having AM on and you have the ability to instantly reapply it without sacrificing any damage.