When "canoe" (meaning kayak and canoe) slalom racing was first standardized floating buoys were used instead of hanging gates. A 4 second penalty incurred if the paddler's boat or body touched a buoy. After hanging gates became standard a 2 second penalty was added if a paddle touched a gate. At that point paddlers started using 90 degree offsets to reduce the chances of touching a gate and getting a 2 second penalty. In that context, at that time, a 90 degree offset was "best" and all the top athletes were using that offset. The paddling community forgot about the context and adopted 90 degree offset as the "best" all around offset.
Wrist injuries were common and people started toying with the idea of less than 90 degree offset. A 1979 of study of Olympic paddlers suggested that 60-65 degrees was "best" for the paddlers studied. However, no extensive research was published to support that claim. Since then there have been almost no studies on the biomechanics, kinematics, aerodynamics, or hydrodynamics of the benefits (or lack of benefits) of offset blade angles. The studies that do exist or case studies of a few paddlers, or have inconclusive results.
All of the "evidence" is anecdotal and, in my opinion, it is created and applied after the fact to "justify" using different offset angles. Reducing wind resistance and biomechanics are the most commonly stated reasons for feathered paddles, even though there is no evidence to support those statements. In reality, it doesn't matter why people use a feathered paddle, as long as it is safe, effective, efficient, and comfortable for them.
Free Standing Boat Racks
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