Thanks for the advice. I’ve been reading the manual on set all day and I think I will get the effect I’m looking for using the Parallel mixer and leaving that at its default setting. Alternatively I will try layer mixing using different composite modes.
I did a quick search for “unmix DaVinci Resolve” and I can only find references to unmixing dissolve transitions to grade both sides of the effect. Is that what you’re referring to or something else?