The thing there is that, for one, a large part of GS damage is crit draw, and for another, sharpness is a /really huge/ modifier when you're dealing with single-hit big damage. Just ignoring it is a kind of silly thing to do.
Your crit draw is worth much less than you think it does, details further down.
The sharpness was left out of the equation since the two weapons had the same sharpness level and so the damage multiplier from it. In my sleepy state I thought it didn't matter and it wouldn't have if we weren't comparing raw with true damage, so both have purple sharpness and that is a 1.44 multiplier so the numbers are now as follow:
Head
GS: (368*1.44)*0.65= 344.448 damage dealt
CB: (672*1.44)*0.65+150= 778.992 damage dealt
Body
GS: (368*1.44)*0.25= 132.48 damage dealt
CB: (672*1.44)*0.25+150= 391.92 damage dealt
Also, nobody actually knows how affinity works. Really. It's not consistently "you get negative crits 20% of the time with -20% affinity" or anything, it's just "you sometimes get negative crits, maybe?" At least, as far as I'm aware. No idea if anybody has figured out exactly how it works, though.
Affinity and crits have been figured out ages ago and are very simple. A crit is 25% more damage, a negative crit is 25% less damage, your affinity is your chance to crit/uncrit. In the case of the GS in the above calculation we have -20% affinity so a 20% chance of dealing 75% damage, which is a 25% damage loss, so 20% of 25% is 5% and so on average this weapon will deal 5% less damage than the numbers would suggest.
Not to mention the fact that, for the CB ultra charge you're calculating multiple hits with...what I think is an average? (Honestly, that part is a bit confusing, clarification would be nice.) That leads to further inaccuracy from the actual damage numbers, considering that's being taken before several other modifiers.
And true damage is just dumb and broken. :|
The various burst attacks from the axe mode cause different numbers of phial explosions after the hit, in the combo you get form pressing AAA the first move has one blast, the second move gets two blasts and the third move gets 3 blasts, the third move is the super blast which you can shortcut your way to in various ways. Note that these burst attacks only use one of your phials each. The ultra burst is something you can turn your super burst into, it will consume your shield/axe boost and all your phials dealing a nasty hit which comes with a frontal shockwave dealing phial blast damage equal to the number of phials you had. The numbers, as far as I'm aware are fine now that the sharpness above is factored in.
True damage has been in the game for a loooooong time, since the first game in fact, barrel bombs, crag/cluster shots, cannons(i think), gunlance shelling and wyvern fire also are partial true damage and I'm not 100% sure about the bow blast arrow, slimeblight/blasblight from things like brachidios weapons are also true damage.
Edit:
OH SNAP! I forgot that since one would have the shield boost on you have to give that charge blade an extra 20% damage
Edit 2: Aaand I forgot that that 20% boost applies to all CB attacks EXCEPT the ultra burst.
Edit3:
If we want to talk about a readily spammable attack, burst 3, or super burst(the thing the guy kept using in the video) is what we should look into when looking at it from a dps/useability standpoint instead of alpha strike power
Math to be added in a moment, please wait...
Edit 4: math is here
The super charge motion value is 0.9 + 3 blasts with 0.1 value each as true/neutral damage
our CB weapon power was 300 so lets do the math again
CB Super burst: 0.9*300 cut + 0.3*300 true= 270 cutting damage and 90 true damage before sharpness
so 270*1.2*1.44 for the shield/axe boost and sharpness respectively for 466.56 cutting damage and 90*1.2(shield/axe boost) = 108 true damage
magala head
466.56*0.65+108= 411.264
to the greatsword's 344.448
magala body
466.56*0.25+108= 224.64
to the greatsword's 132.48
Still not factoring that 5% damage loss on the GS or the bonus element on the CB skewing the number in the GS's favor. Super Burst can also be done right out of a guard which itself will apply a free phial blast for a free extra 18 true/neutral damage(phial blasts outside of Super and ultra bursts get a motion value of 0.05 instead of 0.1). Take into consideration that that the super burst can be quickly comboed into or come out instantly after blocking an attack and you have more openings than a GS user has. You can do something silly like landing 2-3 swords strikes at an enemy about to attack you and at the last moment press the switch button to get an autoguard which then gets you a free phial burst plus a combo-free quick super burst. As long as you learn to use those guarding frames, or guard points as most people call them, you can be suicidally aggressive while staying perfectly safe and dishing out ludicrous damage and knocking out monsters left right and center.
For example, at the moment in low rank I'm using a mixed set giving me Guard+2 and Guard Up which means I can block all attacks in the game and do so easily. These two skills are just as offensive as defensive with the CB and let me keep on trucking... when I'm not screwing up and getting turned into some monster's starstruck plaything that is. Need more practice.