Let's say you have a mesh with two strands joining to produce an arch.
Now duplicate your mesh and then dynamesh the duplicate and sculpt
on that until you are satisfied.Then take that mesh and project it onto
your original two strand mesh.Most likely you'll run into trouble where
the strands intersect,though.Manual fixing needed then.
Could be troublesome in TG,too,again where the strands intersect.
That's all I can think of.