Why Axis technology sharing is not enough

Would better German, Italian, and Japanese technology sharing have prolonged the Axis war effort?

Not much: divergent technical paths, incompatible infrastructure, limited industrial slack, and weak logistics would prevent rapid adoption.

Better technology sharing is judged insufficient to prolong the Axis war substantially. Germany, Italy, and Japan had followed technical paths that could require the recipient to learn much more than the final design. Shared British and American industrial practices and Atlantic problems made some exchanges easier to absorb. Japanese 18-inch gun plans illustrate the mismatch: their usefulness is questioned to Germany in 1944 and notes different preferences in barrel length. British and American manufacturing and logistics are also described as having more spare capacity for adopting ideas. Better information would still leave the Axis needing the physical infrastructure, including docks, to use it.