The point with SMR is to overlap tracks like roof shingles, since the read heads can read a narrower track than the write heads can write. In addition, the hea

The point with SMR is to overlap tracks like roof shingles, since the read heads can read a narrower track than the write heads can write. In addition, the heads have multiple levels of independent actuation beyond the shared arm itself[1][2]. So as long as the tracks themselves are fairly consistent, I don't see why the number of sectors per track has to be equal. [1]: https://pcper.com/2009/09/wd-unleashes-nested-actuator-and-anti-disk-tech-with-two-new-7200rpm-2tb-models/ https://pcper.com/2009/09/wd-unleashes-nested-actuator-and-a... [2]: https://blog.westerndigital.com/hdd-magic-20tb-18tb/ https://blog.westerndigital.com/hdd-magic-20tb-18tb/