I was surfing the net while the site was down  >:( and I found this article on the Ontario MRN site.
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In it they say that landing net 'may' cuase harm by damaging fins and removing the protective fish slime.  Research is ongoing...
I have normally used a net on some species, trout & walleye but for bass and pike I just grab the fish.  

I may consider a gripper if I could manage it easily enough.

good topic it made me think.