When is “teardown” not a dirty word? When the house is a modern stunner perfectly sited in a deep, tree-lined Tanglewood lot. From its inception, the Tanglewood addition was forward-looking, with a legacy of many midcentury gems. The spacious lots and excellent public schools have tempted owners into tearing down mostly ordinary ranch-style homes and building larger houses. This architect-designed house at 2924 Harlanwood Drive is a good neighbor, honoring the original setbacks of the adjacent houses and preserving the tall mature trees. In fact, the stone veneer echoes the style of some of its midcentury neighbors.