I just noticed the subtraction modes names in the merge shader are reversed.
It says Subtract (A - Input) but to replicate that result in functions it's actually: Main input - Input (A) which would actually be Subtract (Input - A) in the merge shader.
I'm unable to reproduce this. Can you show how?
Uhh, no I don't think I can cause I think I just got confused in Hannes wave preset file with all the merges without names. I think I clicked on a separate merge when I was referring to the results.
I just checked again, and they seem to be right, though it's hard to tell in these previews cause of scale of preview.
This one made me chuckle. That's exactly the way I use to work. I just fiddled around with the merge shaders until I got what I wanted without the slightest idea what I was doing and why it worked. ;D ;D ;D
I tend to use the straightforward blue mix/add/subtract/multiply/etc node any time I can, instead of the normal merge shader, which I believe is also faster (a micromillinanosecond).