I didn't realize that landing net is associated with newbies.
Again, it really depends on the landscape, the size of the fish and what you would like to do with the fish.
If you are targeting large chinook salmon, it is probably not wise to have a net with you as the size of the net is too big for carrying around and it is simply not practical to be netting fish in this size range.
Here is Chris landing a white chinook salmon on the Chilliwack River. Notice how he simply guided the fish into the shallow water until it turned to its size. Once the fish did not too much, Chris proceeded to tail it and kept it in the water most of the time prior to releasing. The fish never touched the sand on dry land.
http://www.fishingwithrod.com/video/0818.htmlFor the Tidal Fraser where I use my catch and release net regularly, the intention is not to ensure that I land all my fish, but to keep the fish in the safest manner while I do what I need to do (IDing, photograph, DNA sample collection) prior to releasing it. The net acts as a "cage" in the water by allowing the fish to swim and suspend freely.