The pitch for merging is irresistible: one checkpoint has the faces you like, another has the skin, a third the colour grade, so blend them and keep the best of each. A Civitai author who built a production base that way, then trained a roster of character LoRAs on it, went back and measured it. The findings below are theirs (measured on Krea 2, a 28-block MMDiT); we have not re-run all of them, and we say where our own experience agrees. The block numbers are specific to Krea 2. The failure modes are not.
Academy / Krea 2, photoreal / Lesson 6
Pro lesson · 6 min
Merging checkpoints: where the face lives
Blending two fine-tunes 60/40 does not give you 60% of one and 40% of the other. It can come out worse than both. Here is what a block-by-block view of Krea 2 says to do instead.
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