Inspired by the Trace Eliiot highpass effect loop I came up with Rolls crossover and a blending pedal, I wound up going to 3 channel wounded paw blender to get it hunky dory but a single channel blender works for pedals on same general phase if you put the whole lot into a bypass loop.
Much of the discussion is about the blending, you can go to the end Cheap crossover loop and blend
I cannot recommend this setup enough. It opens up the fuzz end of my Behemoth. It makes Heliotrope "civilised" while going nuts, no mean feat.
I tried using the blender alone for a clean blend. It was incomparable to using the highpass.
Looking at the deluxe big muff, apart from the noise gate mine does everything that does for my whole dirt section. $65 for the Rolls and I got the blender off the classifieds for $140, set for life.