Twin tree coppice

So there I was ready to transplant a honey locust that was too close to its brother, then I thought - why not leave the two trees in place?

Is it a thing to plant two coppice trees in the same spot? The advantages would be that you could coppice the first tree and then coppice the brother tree four years later. I might be wrong, but I think most coppice systems run on a seven year rotation. If you doubled the trees in place then it would theoretically shorten the cycle.

Some benefits of twin tree coppicing would be...
-shorter coppice cycle
-larger size of cut wood
-two trees support each other while they are recovering from coppice
-more efficient use of sunlight by having a short tree by a tall tree
-competition for light may lead to straighter trunks

Possible drawbacks
-competition between trees for resources would lead to weaker trees
-may lead to lopsided trees
-lack of air flow and increased humidity may cause diseases

Can't hurt to try it out. I want to do this on a friend's farm where I've set up a willow pole nursery. The plan is to plant shelterbelts of dual rows and then pollard them one row at a time (keeping the new growth above the browse line). That way the shelterbelt continues to function...as one side is regrowing, the other side is at full height. I think it would work with any fast-growing coppice trees.

In my copse (an area of coppiced woodland) the regrowth on the trees is phenomenal - they reached 4' (1.2m) in the first year and are up at 7 or 8' (2.1-2.4m) now, in their second.

I can't imagine how the stools would cope if there were two competing for the same spot but I am sure the stool with the younger growth would be forced to grow sideways or wiggly, removing a lot of the utility of the wood.

I would suggest that you cut both the trees at the same time and, assuming similar rates of growth, both will grow slightly outwards and then up, towards the light, giving you straight poles with a curve at the bottom. That may be a useful shape in its own right (hockey sticks, brush hook/slasher handles) or you could trim off the curved sections for a straight rod for the usual uses.

I would also expect the two stools to show less vigour than the other, more distantly-spaced stools (assuming you have more trees cut for coppice). This might also affect your rotation a bit.

As Phil says, it can't hurt to try it.