In order to expedite the trial and decision of cases, the court of appeals, when the court deems it advisable so to do, is authorized and empowered to sit in sections of three (3) judges each, at Knoxville, Nashville and Jackson, to hear and determine cases just as though all twelve (12) members were present and participating; and the presiding judge of the court of appeals shall in such event have the right, from time to time, to assign and reassign the judges and sections.