Canniwhatsis I found the name of the technique we was talking about.I'm not sure if it's the correct name in English...anyhow I know its name in Italian is '' approximation graft '' or '' fake graft ''
This picture should explain better....
Some more images in this link
Keep us informed on your work
ps: do you know how some bonsai growers '' create '' such strange shape in their little trees? Simply use this technique with only one plant.Bending a branch and grafting it on another stem
pps: Just discover that this fake grafting is used to change the root mass from a plant that is suffering.
example: If an old lemon tree is suffering at roots level,I can take a young and vigorous lemon tree, plant it near the old one,and after some time start the grafting.
After some more time (don't now how much) the stem of the old lemon tree can be cut and the root mass removed.
So the old lemon tree is still there, but with a young and strong roots