Lots of questions (and I’m sure many of them will be “wait for the rules to come out” type of answers)
I'll do my best
What is the difference between (Unarmed) Brawling and Pugilism? Are they mechanically different? Likewise for grappling?
When making an unarmed attack, the basic Unarmed ability is used, plus whatever specialization and mastery possessed. If the attacker is a pugilist, the style and nature of his attacks will be different than a more reckless brawler. To that point, the difference is narrative. However, the MRV (maximum rank value) of the Pugilism Specialization adds to the Evade Die Pool, which represents the quickness and fancy footwork of a trained boxer. There's also martial arts...
Also, Grappling Specialization adds to Potential-Harm and also improves chances with wrestling maneuvers (there are grappling rules based on opposed rolls).
I see 4 defence pools (Weaponry, Evade, Dodge, and Deflect). I assume you can switch between them in combat. If so, that is a total of 90 points (30+22+12+26) of defence. That seems like a lot.
The defender can only choose one defense per strike against him. Also, the defense type must be suitable against the attack type. Parrying with a kitchen knife against a great axe won't work no matter how high the score in Weaponry. A single attack can penetrate the chosen defense, and still reduce the opponent's Toughness, no matter how many points he has combined. Some attacks, like most forms of magic, bypass active defenses and affect Resilience before Toughness, and often bypasses armor (although sometimes Dodging can be used against area-effect spells with a physical manifestation).
Assume he is battling a similar opponent with Melee D10 > Swords D8 (+2 threat for short sword) giving an average threat point of 16-17. That would be an average of 5-6 attacks before his defence pools are depleted and he must ‘dip’ into his Armour/Toughness, correct?
All it takes is a single attack to penetrate a defense pool. For example, if Weaponry doesn't do the job, the opponent does not get to "switch" to Evade and use that next. No, the excess points cut straight to Toughness, mitigated only by armor.
What is the difference between Dodge and Evade?
What is the difference between Deflect and Weaponry (I assume weaponry is used to parry)?
Evade is used mostly against close attacks, although can be used to evade mundane missile attacks. Dodge cannot be used to escape close attacks, and is in defense of ranged or area-effects only. From the core rules:
EVADE: This defense pool represents advanced close-combat
evasion, by means of sudden or repeated shifts
of place or position, as well as feints, or “rolling
with the punches,” as well as evading most ranged
attacks, all without significant movement. Such
defense represents swashbuckling or acrobatic
maneuvers, or as martial arts skill, whichever best
fits the character concept.
A character cannot use this DP to evade magical
attacks or area effect spells of any kind. Also, note
that wearing medium armors only allow half of
the Evade pool in a battle, and heavy armor would
disallow it entirely.
DODGE: This defense pool represents avoidance of harm
by means of sudden bursts of movement, and is
a measure of how well a character can anticipate
and move his body out of the path of danger.
Characters can dodge missile weapons, dangerous
area spells or explosions, or a charging foe (such as
a knight charging on horseback).
This maneuver cannot be used to reduce the
Potential-Harm of close-combat attacks (whether
melee or unarmed). Dodging while engaged in
close combat provokes an opportune attack, with
few exceptions (see below).
Weaponry Defense represents defensive actions
made with weapons to deflect a melee attack. This
includes actions such as parry, entanglement (as
with a length of chain or a whip), and keeping an
opponent at bay by means of a reach weapon (such
as with a polearm, bo-staff, or long spear). This
category is the abstract score of a character’s overall
knowledge of weapon-based defensive maneuvers.
The Deflect active defense pool uses the base Melee
skill MRV as its base, because any creature can pick
up an appropriate makeshift object and use it as a
shield. Having actual shield skill adds to this DP.
How does max-split work?
From the Quickstart Guide (in revision now):
A character normally combines the dice of a combat related ADC into a single attack (like 1D4 Melee + 1D4 Bludgeons = 2D4 attack), but may also split the dice to make separate strikes (1D4 attack & another 1D4 attack). Why would a player want to split attacks? Splitting attacks allows the targeting of multiple enemies within range, and allows the application of weapon-based harm bonus several times. The specific weapon type limits the number of times the wielder can split the dice pool (see “max split” equipment chapter).
While that may sound like a player would want to split all their attacks for the added bonuses, remember that the defender chooses a defense after the attacker rolls for each separate strike. Splitting attacks means that each attack will tend to result in lower threat points, so damage reducers like armor and shields can easily block the attacks. To restate, multiple attacks allowing one to apply a weapon’s harm bonus applies to each separate die, and the option of choosing different targets within the weapon’s range all counterbalances these disadvantages.
As mentioned, each weapon is listed with a statistic called “Max-Split”, which denotes the maximum number of times an ability branch (ADC) can be split into multiple attacks, each independent die roll representing a separate strike.
For example, Sir Hurtalot wields a Kris Knife, which has a “max-split” of 3. If Sir Hurtalot had an ability branch of Melee (D10) > Knife (D8) > Kris Knife (D4) could split his ADC into as many as 3 separate die rolls, and add the knife’s harm bonus of +1 to each attack.