I searched the canyoneering sites to determine what shoes were reported to provide the best traction when using a river as a pseudo trail. Only two shoes were consistently mentioned as providing adequate traction for safe travel. The Five Ten Canyoneer II was first with the La Sportiva Exum River a close second. Both of these shoe’s soles are manufactured from proprietary soft rubber formulated for cold water rock traction. There were many comments about conventional " so called water shoes", such as the Solomon Techno Amphibians, providing lack of acceptable traction on wet rocks in cold water. The standard for dedicated fly fishing shoes is felt soles. The consensus in the fly fishing forums I searched was that the Stealth Rubber licensed from Five Ten and used on some wading shoes provided about 80% of the traction provided by conventional felt soles.
I would like to establish a BPL testing protocol that forum members would use test cold water rock sole traction. This protocol should allow meaningful comparisons between different testers. One idea that came to mind was to fill up a plastic bag with on quart of water. Place the bag inside the shoe. Place the shoe in the refrigerator for one hour prior to testing to simulate the typical 55F degree water for trout. Place the shoe on a wet, smooth, and level polypropylene plastic surface. Pull the shoe across the plastic with a fish scale connected to the laces, or push with a postal type scale across the plastic sheet, to determine the traction provided. Larger size shoes would test with more friction than smaller shoes but we should still be able to determine a general sole type friction range for a given size shoe, given enough testers. We would each publish the test results for the shoes that we own to this forum for comparison.
I strongly suspect that are better test protocols than the first one I came up with and so I would like to hear others ideas before beginning testing the shoes I currently own. Hopefully we can approach consensus on a single test protocol.