(a) Corner Lots. Where front yards have been established or may be required on each of two intersecting streets, there shall be a front yard on each street side of a corner lot, with the following two exceptions:
(1) In R Districts, where established front yards exceed twenty-five feet, only one front yard in excess of twenty-five feet shall be required.
(2) The building width of a lot of record need not be reduced to less than twenty-eight feet when the owner of such lot can show that ownership and control of any adjacent lot or lots of record are by another person.
(b) Through Lots. In the case of through lots, unless the prevailing front yard pattern on adjoining lots indicates otherwise, front yards shall be provided on all frontages. Where one of the front yards that would normally be required on a through lot is not in keeping with the prevailing yard pattern, the Zoning Administrator may waive the requirement for the normal front yard and substitute therefore a special yard requirement which shall not exceed the average of the yards provided on adjacent lots.