Understand the count you received
In the owned example, one mesh resource contains 12 triangles. Placing that resource twice produces an expected resolved total of 24 triangles. This is a count of placed geometry, not a second stored mesh resource, a print-quality grade or an estimate of toolpath time.
Compare one placed cube with two placed cubes. These owned packages demonstrate instancing. The guide retains a separately labelled local processor observation; it does not establish the deployed endpoint revision.
Triangle count alone does not establish toolpath time or physical print quality. Compare critical surfaces at the intended size and use the actual slicer outcome before claiming a performance improvement.