For some of the standard guild questlines, I had to rearrange the list of dialog responses so that the default (no conditions) dialogs were really at the bottom of the list. For those that don't know, the Skyrim engine runs down through the list of possible dialog responses an actor will give and finds the first one that matches all conditions. If there is nothing, the actor has no response to you. Therefore, if you place a response with no conditions to it, the actor will always have that response to give.
Having said all this, to fix some quests, I had to move responses out of a topic and then move them back in so they shifted to the bottom of the stack/list of possible responses. This allows for better organization. However, I'm looking at possibly adding some more dialog options and finding that because they are added automatically to the bottom of the list, they will never be said because the game as a dialog response above it which will always be said first.
Without messing with the order of the existing responses, how do you insert a dialog topic into the list/stack without it always being at the bottom? Is there a way for an ESP file to insert a dialog into the top of the dialogs of the master ESM file?
For example, if you have asked almost anybody in Skywind for their Background, you have probably gotten the "My background is obvious" response. That is because is the is bottom default response. Actors that have responses specific to them "My name is Valus, and I am a guard", are already listed above this default and have conditions for that actor to use that response. What if I wanted to create a mod that adds Background responses to members of the mage guild or something else? By default, those are added to the bottom of the list of responses. I want them added above that default response. But I don't want Digitalparanoid to have to merge these into the ESM file of Skywind just to have this done. There has to be a better solution. Any ideas? I can't seem to get CK to do it without resorting the list by moving responses to another topic and then back again.

I totally understand where come you from. I don't know how any way other than to put the new topicInfo at the end of the stack and then move them up if necessary. The "catch-all" topic info should obviously be the last. For those "generic" topics in which you want to add new dialogue, you can do that, I don't see a lot of issues in merging them (that is if the CK behaves ;) )
(Well, there is actually a work around if you copy a topic and modify the duplicate, you can have a new record in the middle of the topic list without updating all the other topic infos above and below... - Just be careful not to duplicate topicInfos with scripts because it will duplicate them as well)
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This is a bit off your topic nut another remark is that actually, if you go back to morrowind esm, you will see that most dialogue conditions are basically thought with the ones above in mind.
exemple
T1 getStage > 15
T2 getStage > 5
in T2, getStage < 15 is implied (otherwise T1 would be played). That is simple. Some cases are trickier.
In morrowind, you learnt about the topics through "hyperlinks".
However in Skyrim/skywind, you have access to all the running quests' dialogues for which the conditions match (including the quest dialogue conditions on 1st tab) so it's a very different approach.
Morrowind you now nothing and topics will appear progressively. Skyrim/Skywind you now everything by default and conditions prevent you from showing everything.
Due to that, we have to enforce much stronger conditions on dialogues. This is a WIP on my side but all working on quests/dialogue should think about it too.
Damn, that sounds like a big job...
Just pointing out here that you don't have to move the dialogue responses out of the topic to move it to the bottom. You can move them with the left and right arrow keys on your keyboard. Unless I totally misunderstood what you were asking...
I think the question was "how to put a topicInfo in the middle of the stack without editing all the other ones, and therefore have simpler esp files to merge". The workaround is to duplicate an existing topicInfo.
The use of conditions I've become very familiar with during all those guild quests. That was actually part of my problem. I don't want to "break" that structure. I need to add dialogs into the right spot but also keep those chain of conditions applicable. That is why inserting the dialogs right above the last dialog (the one that usually has no conditions) allows me to keep the flow of the quest working correctly.
I'll try to use duplicates and see what that does to the stack. As for scripts, yeah, I discovered that the other day. Kind of ugly to fix.