In theory if you could twist them evenly, you could size a crimp lug for the total cross sectional area. The goodness of the crimp and the quality of the job would be suspect though because of the difficulty of combining the two wires and controlling strain. They would need to run parallel probably 20 diameters before the twist to be ok, and taped or wrapped to that point.
If probably look to use a heavier gauge feeder and then a terminal block or some other type of splice elsewhere.