This image shows two other methods for reinforcing joints in a curve during construction.
On the left, a short section of wood bridges a Homasote joint on the inside to move the load away from the weak spot. This reduces the possiblity of a kink developing or one of the spline laminations breaking.
The one to the right is reinforcing the outside of the curve until I can put some screws on either side of the joint. Normally I would use a Homasote reinforcing splice on the outside, but there will eventually be a second main through here which will take care of the reinforcement duties.