Using the powers of my brain in analysis, these are the issues I see with diplomacy in the current (1.0.0.62) version of Civ5.
There is a lack of understanding on behalf of the players on the diplomatic concepts.
1. How do pacts of secrecy work? What constitutes breaking the terms of this pact? Is the pact different from pacts of cooperation?
AI leader awaraness of events is a mystery.
Does it know...
1. I have pacts of cooperation with others?
2. I trade resources with others?
3. I end deals with others?
4. I break (backstab) deals with others?
5. I was declared war or was declared war upon?
6. I liberate a city?
7. The strength of my military?
8. What wonders I have?
9. I gift units to a third party it is at war with?
10. What culture I have?
11. My open borders deals with others?
12. I intentionally put my units to block its army or trade networks?
13. My technological level?
14. My production capability?
15. I take out barbarians OR other hostile civ units just outside or inside its cultural borders?
16. I explored more of the world than it did?
17. I demand tribute from others?
AI leader reaction to that which it is aware of is a mystery.
See the entire list above. Since it is not known what it can/cannot be aware of, one may frequently do things that pleases or displeases it unknowingly. Further, even if one is aware of that it can know and take into account these events, it is still unknown if it considers it good, neutral or bad. For example, will ending pacts of cooperation displease it? A lot? What about if I break pacts with others it is cooperating with? What if I declare war on someone who it dislikes/is afraid of? What if I gift units to third party? What if I demand tribute from someone it is friendly with? What if that third party accepted/rejected my demand? What if I ask/demand things from an AI that I don't have cooperative pact with? What if I have an agreement when I demand? Offended when? How much? What if I declare war on someone when asked to, but I don't actively participate in the war at all and make peace as soon as I am able to? What if I say "give me 10 turns" then don't go through with it? What if I say "You'll pay for this" as answer to its transgressions towards me, with a military either much weaker or much stronger than it? Does having the same or higher score as the AI make any difference? Being close to a victory type? Having too many allies? Declaring war on third party they are already at war with? Does it like us giving them free stuff? What if we turn down requests for handouts or demands of tribute?
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Summarily, we who do not have developer level insights into how the system works will probably find the diplomatic system puzzling and inconsistant. We lack understanding of what level of information/comprehension the AI leaders have, and even more so how these things will (or won't) affect their attitudes. I think this is behind the frustration expressed in the forum with topics like "Diplomacy is nonexistant, you can't affect anything, they always hate you somehow".
Versus another human, we know what they can know and can't know. They see what we see. Different humans care about different things of course, but they are probably more predictable and reasonable to deal with.
Recommendations:
Make available information on what AI can be aware of and how it typically sees such things. Tooltips in the diplomacy menu can be helpful. Extending the advisors to be able to see them whilst in diplomacy talks, with useful advice on what the other party may be happy/pissed about and what we can do to remedy/escalate the relationship.
There is a lack of understanding on behalf of the players on the diplomatic concepts.
1. How do pacts of secrecy work? What constitutes breaking the terms of this pact? Is the pact different from pacts of cooperation?
AI leader awaraness of events is a mystery.
Does it know...
1. I have pacts of cooperation with others?
2. I trade resources with others?
3. I end deals with others?
4. I break (backstab) deals with others?
5. I was declared war or was declared war upon?
6. I liberate a city?
7. The strength of my military?
8. What wonders I have?
9. I gift units to a third party it is at war with?
10. What culture I have?
11. My open borders deals with others?
12. I intentionally put my units to block its army or trade networks?
13. My technological level?
14. My production capability?
15. I take out barbarians OR other hostile civ units just outside or inside its cultural borders?
16. I explored more of the world than it did?
17. I demand tribute from others?
AI leader reaction to that which it is aware of is a mystery.
See the entire list above. Since it is not known what it can/cannot be aware of, one may frequently do things that pleases or displeases it unknowingly. Further, even if one is aware of that it can know and take into account these events, it is still unknown if it considers it good, neutral or bad. For example, will ending pacts of cooperation displease it? A lot? What about if I break pacts with others it is cooperating with? What if I declare war on someone who it dislikes/is afraid of? What if I gift units to third party? What if I demand tribute from someone it is friendly with? What if that third party accepted/rejected my demand? What if I ask/demand things from an AI that I don't have cooperative pact with? What if I have an agreement when I demand? Offended when? How much? What if I declare war on someone when asked to, but I don't actively participate in the war at all and make peace as soon as I am able to? What if I say "give me 10 turns" then don't go through with it? What if I say "You'll pay for this" as answer to its transgressions towards me, with a military either much weaker or much stronger than it? Does having the same or higher score as the AI make any difference? Being close to a victory type? Having too many allies? Declaring war on third party they are already at war with? Does it like us giving them free stuff? What if we turn down requests for handouts or demands of tribute?
----
Summarily, we who do not have developer level insights into how the system works will probably find the diplomatic system puzzling and inconsistant. We lack understanding of what level of information/comprehension the AI leaders have, and even more so how these things will (or won't) affect their attitudes. I think this is behind the frustration expressed in the forum with topics like "Diplomacy is nonexistant, you can't affect anything, they always hate you somehow".
Versus another human, we know what they can know and can't know. They see what we see. Different humans care about different things of course, but they are probably more predictable and reasonable to deal with.
Recommendations:
Make available information on what AI can be aware of and how it typically sees such things. Tooltips in the diplomacy menu can be helpful. Extending the advisors to be able to see them whilst in diplomacy talks, with useful advice on what the other party may be happy/pissed about and what we can do to remedy/escalate the relationship.