What are those new "Copy config from" settings in the Checkpoint Merger Tab and how is it to understand?

[Orisen]

Hi!

I noticed some new settings in the checkpoint merger tab and was wondering, beside the obvious description, how they work exactly.

1. What "config" gets copied from the checkpoint? What exactly is this?
2. When i choose "A, B or C" do i get the a config from A AND B or C or is it more random like A OR B OR C?
3. Do they work together with the other settings like the Interpolation Method and the Multiplier?
4. And as soon it is clear what "config" gets copied, choosing "B" or "C" is relativly straight forward, but why are there no option for only choosing "A"?
5. Let's imagine i'm merging with "Add difference" and i want to copy the "config" only from my primary Model A than i don't have the option to do so. Or does it even work like that?
6. And the maximum confusion get's actually caused by the 4. option "Don't" which states to me that this stuff is totally optional?

So, i'm interested into the behind the scenes stuff when choosing one or the other option. Because i think by understanding what is actually going on in the background, when merging checkpoints together, can help to produce better merges.

Unfortunately there is no wiki page for the checkpoint merger and all his settings. If somebody could explain those new settings to me, i would appreciate it a lot.

Thanks!

[vladmandic]

for any sd v1.x model, its irrelevant as v1 config is assumed by default.
but sd 2.x models require config files and instead of manually creating one for each model created by model merge, it copies the config from the original model used for merge.

[AdvaitaSprite]

. . . but sd 2.x models require config files and instead of manually creating one for each model created by model merge, it copies the config from the original model used for merge.

Thanks, this went a long way towards answering my question as well. But I'm still a bit confused about it (as pertains to v2.x models). What does the "A, B, or C" option mean? It's confusing to me that there's an "A, B, and C," a "B," and a "C," but no "A..." And if it said "A, B, and C" then I'd just assume it was merging config files for all of the models involved which have one available, but since it says "or" it sounds like it just arbitrarily picks one at random. Is that what that option does?.. Or does it mean something else? Is there a particular method/guideline to know which model's config file you'll be better off copying in a given scenario? Also, when is it better to integrate a VAE vs not doing so?

Thanks very much.

[vladmandic]

A, b, c refers to merger itself.
Copy config is from a to target and that's it.
B and c have to be same type of a model anyhow (so same config) or merge cannot work.