Great idea! However I feel its cheating to use it in increasing the life of deut. My factory :( Anyway, still worth a slot, for once someone hasn't been suggesting elements like one-pixel thick E-Walls or Gold and Protons.
A DEUT-Compressing factory? Not too hard to accomplish with CFLM and PIPE, though. Or, you could put fire on EDIT, and the fire would burn for as long as you want (fire disappears when its life is 0)... Candles!
There's something like this in my mod. Each one can only give one property, but it uses flood-fill so you can edit a lot of particles at once. It's called PWHT (powered heater), but to use it like EDIT, you just use the PROP tool on it. It would be nice if this got into the official version, there haven't been many new elements recently and this one is useful.