Lawrie Bloom, solo bass clarinetist of the Chicago Symphony Orchestra, starts this video talking about his reed break-in process, but spends some time toward the end (start at about 2:45 to cut to the chase) talking about his strategy for doubling clarinet and bass clarinet in a symphonic setting.
Mr. Bloom recommends using slightly softer reeds than usual to compensate for the fact that the reeds will be somewhat drier than optimal, and using a mouthpiece cap whenever possible.