With respect to fiber optic structured cabling, dense optical termination and patching platforms, systems, and methods herein involve using an optical-connector adapter cassette that has double rows of adapters on a front portion and at least one goose-neck portion that transitions to a single row of adapters on a rear portion. The double rows of adapters may have virtually no geometry between them. Two cassettes may be cantilevered at the front of a fiber-optic enclosure. The systems includes other aspects.