The LOWER UNIT made the Outboard product & industry a success.

[Lake X Kid]

A major contribution to the Outboard’s functional success and a popular consumer product is the Lower Unit. I will assert, without the lower unit there is no outboard industry as we know it. The lower unit made the Outboard a Big player for boaters.

The marine industry (especially marine dealerships & the OEM employees at Merc, OMC, etc.) are beholden to the lower unit. Also, the lower unit made MerCruiser products a viable marine option for boaters, and a propulsion industry success.

[Chaz]

I believe it was OMC who designed the bullet (sporty) nose housing. Instead of running to the patten office, they did away with the concept .. because it got caught up in vegetation above the bullet rather than just passing over it ...

[XstreamVking]

Back in the 70's little mercs had a "swept skeg" design. They were designing a set back into the engines. Claimed to shed weeds better. I had several little mercs and johnrudes of various hp ratings. Mercs were always faster than the johnrudes on the same boat I believe partly because of the lower unit setback.

[keith scotton]

Clay Conover an omc engineer designed the first shiftable lower unit late 1940's. He was related to the Johnson Family.

[keith scotton]

Johnson outboards had first cavitation plate. First saltwater lower unit it had a brass case. 1922 to 1924

[Scream And Fly]

I agree. I think it's easy to underappreciate just how central the lower unit is to outboard performance and overall running quality.