Time-domain Wavelength Interleaved Networking (TWIN) is a cost-effective network architecture that can provide fine-grained, flexible connectivity using passive optics in internal nodes. Each wavelength is dedicated to carry traffic to a single node. We introduce TWIN with wavelength reuse (TWIN-WR), an extension of TWIN that allows the number of nodes to exceed the number of wavelengths. We formulate an associated design problem, decompose it into subproblems, and provide algorithms for solving the subproblems. We experimentally demonstrate that our algorithms come close to upper bounds over a wide range of parameters, and show that the resulting designs are robust in the face of traffic variability and uncertainty. Analysis and experiment show that high efficiency can be maintained as long as the number of nodes does not exceed the square of the number of wavelengths, in principle allowing a network with thousands of nodes using only one hundred wavelengths.