So I was trying to figure out which sigil would benefit me the most, so I tried to do some basic math to find out, and here is my attempt:
If Damage = D, Critical Chance = C, Critical Damage = X, and Power = P (P is only included for fun, like weapon strength, armor, coefficient and such, they will be the same for both sides so should be omitted)
When using the sigil of accuracy, our damage is this:
D = (C + 0.05) * X * P = CXP + 0.05XP
When using the sigil of force, our dmage is this:
D = 1.05 * C * X * P = CXP + 0.05CXP
When we compare both of them, we can take CXP away since it's the same for both, so we end up comparing 0.05XP (Accuracy) to 0.05CXP (Force), ultimately that boils down to:
1 (Accuracy) vs C (Force) => every time C is less than one, you will do less damage than the other option; since you rarely have 100% critical hit chance, the "1" option will always give you more damage
Thus, the sigil of accuracy, which means increasing 5% critical chance, is always better than just increasing 5% damage, this also implies that +100 precision will always be better than +100 power UNLESS:
1. You cannot critically hit your enemy
2. You have more than 100% critical hit chance
3. Your attack is sooooooooooooooooooooooooooooooooooooo slow that you will rarely crit , ever. <= In this case you will do more damage in a very very long period of time, which becomes impracticable due to the duration of each encounter in GW2
I feel like this is not a very extensive calculation but it's the most intuitive and direct for what I can come up with, what do you guys think :O ...
This also brings about the topic of the illusion of damage, people often feel like 30% crit chance, or 50% crit chance is the sweet spot, but in reality damage also relies heavily on power , critical damage and attack speed; from math it would seem like the higher the crit chance the better the damage no matter how you look at it as long it's equally trading stats ( 1% for 1%)
But I think the reason people have a feeling on where it's the best, could be contributed by the attack speed, which is another key part to damage, but the part players cannot really control since only ”Quickness" can affect this in game (from what I know); which I think refute the point that, eventhough you might have higher damage, if you're attack is really slow, in the duration of your fight you will not feel much from critical damage. We are given 50% critical damage to begin with (1.5 base crit mutiplier) , you can see that as 1000 Power; so the more your crit chance approaches 100% , the more you get access to this 1000 power in a shorter duration of time, and the more crit chance you have, the more it feels like you are getting access to this damage in your duration of fights.
The problem is, if you attack infinitely fast, you can access all your hidden power anyway since it will crit before you know it; and again, this is the feeling of time; the faster you attack, or the more chance you have to crit will affect how you feel about your access to your 1000 power + any crit damage you added.
So since we can't control attack speed, we can only improve on critical chance .