(a) Purpose of hearing. The purpose of any hearing the commission conducts under chapter 54 of the general statutes shall be to provide to all parties an opportunity to present evidence and argument on all issues to be considered by the commission.

(b) Order of presentation. In hearings on complaints, applications and petitions, the party that shall open and close the presentation of any part of the matter shall be the complainant, applicant or petitioner, unless otherwise provided by the commission or the presiding officer for good cause shown.

(c) Limiting number of witnesses. To avoid unnecessary cumulative evidence, the commission or the presiding officer may limit the number of witnesses or the time for testimony upon a particular issue in the course of any hearing.

(d) Written testimony. The commission may by order of the presiding officer permit any party to offer testimony in written form. Such written testimony shall be received in evidence with the same force and effect as though it were stated orally by the witness who has given the evidence, provided that each such witness shall be present at the hearing at which testimony is offered, shall adopt the written testimony under oath, and shall be made available for cross examination as directed by the presiding officer. Prior to its admission such written testimony shall be subject to objections by parties.