So. Specialisation vs. generalisation. The issue here is fundamentally one of opportunity costs. We can only get so much xp at a time. If one spends that xp unwisely, then one falls behind others who are spending it more effectively.
Let's illustrate the issue with a simplified example.
We could, crudely, describe the core combat statistics of a cultivator as:
- Physical attack
- Spiritual attack
- Physical defense
- Spiritual defense
Obviously it's more complicated than this, and there are things like Tests that also need to be accounted for, but this will do for now.
Any cultivator has a limited amount of xp and arts that they can allocate to increase their core statistics. Let us imagine that a green cultivator has 120 points or dice they can allocate to their main stats. The even "general" build would be:
- Physical attack: 30
- Spiritual attack: 30
- Physical defense: 30
- Spiritual defense: 30
Now. What if we specialise? Realistically, it would be foolish to skimp on defense, since you don't know what your potential enemies might use against you. However, it is an easy choice to focus on 1 form of attack. A more focused build could be (Focus A):
- Physical attack: 40
- Spiritual attack: 0
- Physical defense: 40
- Spiritual defense: 40
Such a build would destroy the generalist every time. The "generalist" would be unable to leverage his spiritual attack to any advantage, because by dropping spiritual attack the focused build has been able to get even higher spiritual defense as well. In all relevant combat statistics, the focused build has the advantage. Simply put, the focused build is able to apply their strengths, and there is nothing the generalist can do about it.
Now, what could cause problems for the focused build? What if they ran into someone that had sacrificed their spiritual defense?
Well, if someone who sacrificed spiritual defense for attack like below would not have an advantage (Focus B):
- Physical attack: 40
- Spiritual attack: 40
- Physical defense: 40
- Spiritual defense: 0
This match would be very even. However this build would lose to the generalist, who would be able to leverage his 30 dice advantage on spiritual attack, and really would be asking for trouble from any enemy with spiritual attack. So one is unlikely to encounter anyone who would try this.
What about a more specialised build? What would actually cause trouble for someone who's sacrificed their spiritual attack?
Maybe something like this (Focus C):
- Physical attack: 50
- Spiritual attack: 0
- Physical defense: 50
- Spiritual defense: 20
By shifting points from spiritual defense (which wouldn't be being used) an even more specialised build can gain a physical advantage over our first focused build. This build would still have an advantage over the generalist, having a 20 point advantage on physical attack while only suffering a 10 point disadvantage in spiritual.
Of course, Focus C would lose to a build that instead had high sp.atk and high phys.def:
- Physical attack: 0
- Spiritual attack: 50
- Physical defense: 50
- Spiritual defense: 20
Which just goes to show that there is always a counter-build to whatever build you choose.
On the whole though, the specialist build will nearly always have an advantage over the generalist, unless you're stupid enough to do something like Focus B.
This discussion, of course, was all based around the idea that you're putting points into, say, physical attack in general. However, in reality people focus on particular weapons and styles. If, say, you were to do something like spread your physical attack arts out between swording and archery, with limited synergy between them, then your effective statistics would be even lower. Despite having spent, say, 30 points on physical attack you might only be able to leverage 20 of them against someone at any one time, leaving you at a decisive disadvantage against anyone who didn't dilute their abilities like that.
At the end of the day, what you want to do is try to leverage your style as broadly as you can. If your an archer, then you get arts that allow you to use that at all ranges, and that give you options like single target sniping, aoe, disables etc. -
all building upon and using the same passives. If you're musician, you don't go and get a bow for long range - you get more music arts that give you that option!
And remember, you don't have to be able to do everything yourself. That is why we have friends.
Edit:
The hill people have chosen to die on in terms of "not generalising" though is even worse than this. At least with "spritual vs physical" there is an actual interplay and tradeoff, with some builds being countered by other builds. In reality though, if we put, say, 40 points into music then we end up with a bunch of music arts that all reinforce each other and which could be spiritual and physical. So Music 40 actually gives us phys.atk 40 and sp.atk 40. And what is someone going to do about that? Specialise in anti-music defense? If someone was dumb enough to do that we can a) sic our spirits on them, or b) sic one of our non-music using friends on them and laugh. Because specialising in anti-music defense would actually be overspecialisation. But that's not what we're doing here.