[mlangsdorf]

DFRPG: Exploits p30 is explicit that All-Out Attack: Double lets you make two attacks against one foe.

DFPRG: Exploits p36 is equally explicit that you may trade one and only one attack for a dual-weapon attack, and you cannot Rapid Strike during the same turn.

DFRPG: Exploits p38 is equally explicit that you may trade one and only one attack for a Rapid Strike, and you cannot make a dual weapon attack during the same turn.

DFPRG: Adventurers p49, under Extra Attack, summarizes all the above information and includes the page references.

He's very wrong, but if you have the DFRPG, you could have easily looked this up yourself.

The best a swashbuckler or knight can do in DFRPG is 5 attacks: All-Out Attack Double for 3 with 2 of the strikes suffering Rapid Strike or Dual-Weapon Attack penalties and 2 Extra Attacks. Assuming a Weapon Master making a Rapid Strike, he rolls 3 attacks at no penalty and 2 attacks at -3.

ninja to Torvsen:
You can't stack penalties on Rapid Strike to make multiple attacks. It's one attack becomes 2 attacks at -6. It's not one attack becomes X+1 attacks at -6*X total penalty. I can see how you might read it that way from the Basic set, but the DFPRG is very explicit.