The HPLIM wasn't necessarily the first linear op. This is why I classify it as a dumb design. In the NA region, Armor, Westinghouse, and Otis (7660 and 7777A) Mont. WG (similar to 7660) all produced linear operator starting from the late 60s. Even those were more closer in design to the modern linears we see today, such as MONXT, AMD/LD-16, Fermator, etc. HPLIM was just an overbuilt waste of resources.
