If by reason of death, sickness, resignation, removal or other disability, a judge before whom an action has been tried is unable to perform the duties to be performed by the court under these rules after findings of fact and conclusions of law are filed, then any other judge regularly sitting in or assigned to the court in which the action was tried may, on assignment by the Chief Judge, or in case of disability of such Chief Judge, by the senior judge of the Administrative Committee present and qualified to act, perform those duties; but if such other judge is satisfied that he cannot perform those duties because he did not preside at the trial or for any other reason, he may in his discretion grant a new trial.