This is how I get bonus fish with Rodfendr.
When I'm fly fishing form my boat I use Rodfender rod rest to protect another rod which I place in the opposite direction. I can't use the traditional rod holder because I will get my fly line tangled in it. I place my fishing rod between the oar lock with Rodfendr protecting the rod and line from damage and continue to fly fish as normal. I check the second rod periodically and often get a bonus fish as you can see form the video.