OK. I tried my own solution to puting a floating dock at the end of a skinny gang plank. I built a fixed dock partly on the shore and connected it to a floating dock with a 3 ft gang plank. I kept it from roaming with two chains run diagnoly (mispelled) from th fixed dock to the floating dock. I used turnbuckles to tighten these chains (under the gang plank). After 5 years, I conclude it was a success.