In his post, mortetvie made is abundantly clear, with great precision, intelligence, and examples, why it is that there is no conflict to be found and thus why citing AB>BRB simply is not, at all, a basis for making a decision on the rule. How anyone can read mortetvie's post and still cling to any argument in favor of multiple attacks in support as a result of this Special Rule is beyond me.
No, he did make some arguments which fall apart under closer inspection.
While I kind of agree with his counterarguments to point 1 and 2, I also think these are irrelevant to the discussion. Point 3 is the important point and he failed to counter this point.
The argument pro PF working with supporting attacks, is that the moment you roll a 6 for your supporting attack a conflict between the PF and the supporting attacks rule arises:
"Whenever a model with this special rule rolls a 6 To Hit in close combat, it immediately makes an other attack; roll To Hit and To Wound as normal."
vs
"To represent this, he can only ever make a single Attack, regardless of the number of attacks on his profile, or any bonus Attacks he might otherwise be entitled to because of special rules or other unusual effects."
You can not apply both of this rules at the same time, if you just rolled a 6 for your supporting attack, as you either have to "immediately make an other attack" or "can only ever make a single Attack". Therefore a conflict arises and the army book rule overrides the rule book, as per page 11 of the rule book.
This argument is normally countered by someone by citing the latter half of the supporting attacks rule "or any bonus Attacks he might otherwise be entitled to because of special rules or other unusual effects." (often in capitals, bold and underlined), but this half of the rule has really no relevance to the argument, as the rule already forbids more than one attack from subsequent ranks. People seem to think that this sentence somehow overrides the PF rule because it specifically mentions special rules and PF is a special rule, but that is not true. The first half of the rule already forbids more than one supporting attack and therefore the latter part is unnecessary.
Mortetvie tried to counter this argument by creating an artificial difference between the term (close combat) attacks and supporting attacks, by saying:
"Attack"; does not necessarily mean"Supporting Attack"; as not all Attacks" are "Supporting Attacks" but "Supporting Attack" necessarily means "Attack" because all "Supporting Attacks" are "Attacks."
He therefore argued that the term attack in the PF rule does not automaticly qualify the model to make a supporting attack.
The Rule book states the following:
“Warriors in the second rank do not sit idly by whilst their comrades battle away, but muster forward to strike blows of their own. We refer to the attacks made by these models as supporting attacks.”
So attacks made by models in subsequent ranks are referred to as supporting attacks, but is not then every attack made by models in subsequent ranks a supporting attack by definition? I am no laywer but the way GW uses the term (close combat) attacks implies to me that they also refer to supporting attacks.
From the dark elves army book:
"Muderous prowess
Models with this special rule (but not their mounts) re-roll all To Wound rolls of a 1 when making close combat attacks."
So the wording is similar to the PF rule as GW refers to "close combat attacks", but if mortetvie is right and this wording excludes supporting attacks, does this mean that murderous prowess applies only to the first rank?
Good luck explaining this to your dark elf opponent.
I bet other rules like ASF or hatred have the same wording but I am to lazy to search the exact text. We can therefore conclude that the term close combat attacks in the PF rule also refers to supporting attacks, which counters the argument of mortetvie.
Mortetvie furtheron tries to apply both rules at the same time to proof that this can be done without creating a conflict:
"models attacking other models in base contact can benefit from the predatory fighter special rule because there is no restriction on what special rules apply in this circumstance but because supporting attacks are a special kind of attack that says 'no special rules apply' and because predatory fighter is a special rule, predatory fighter does not apply to models making supporting attacks because of the restrictions imposed by the supporting attacks rule."
So models in the first rank can make PF attacks because no restrictions apply. So far so obvious.
In the second part he says that PF does not apply to supporting attacks because it is a special rule and the supporting attacks rule does not allow special rules to increase the number of supporting attacks. I am sorry but this is not applying both rules at the same time, this is applying one rule and ignoring the other: "Whenever a model with this special rule rolls a 6 To Hit in close combat, it immediately makes an other attack".
IMO you can not apply both rules at the same time if you roll a 6 for a supporting without creating a conflict, which triggers the army book over rule book rule.
As an additional note Jeremy Vettock supposedly said at Games Day Cologne that the PF rule was meant to override the rulebook.