I honestly don't see the need for an EEF stone in the field. Chances are if I need to resharpen a knife in the field, an EF stone usually does the trick. If I have gone beyond dull to the point I have done a bit of damage to the edge (chip/roll), then I want the F stone to remove material faster, then finish with the EF. To me, having an EEF stone (in the field) serves no purpose, unless I am bored and feel the need to shave some hair off my arm and then try to split those hairs. Which is never.
In my experiences in the field, an edge sharpened to EEF (let's call it 1000+ grit) becomes an EF edge (let's call it 600 grit) very quickly. So, again - I don't see the need to have a 1000+ grit finished edge for a knife that is going to see a lot of field/camp/hunting/bushcrafting use. They don't stay that way long, and offer no real advantage for typical field chores. Give me a 600 edge any day, all day for a field knife.
I do like the DMT diafold, and always have one with me when out in the wilderness. But a F/EF suits me just me fine - I have absolutely no need for an 8000 grit edge in the field, which I believe is what the DMT EEF is.