Knowing angling techniques and etc is very appropriate for fishing itself, but learning some environmental science (specially when it comes to the aquatic cycle, rivers, waterfalls, hydraulic force, etc) is definitely plus knowledge that may increase your success in catching fish. As a matter of fact, all the fish I caught today at the Schuylkill River was withing 2 feet from where I was standing. Note that this does NOT mean that fish are not present in the river's outwards! Today a guy fishing there caught two channel catfish on clams, casting far outside.
I started my session today at 9 a.m., loaded with nightcrawlers. I was really expecting to fish eel for bait, as I use it a lot to catch catfish at the Schuylkill and the Delaware river. People usually hate to catch eels for two main reasons: (1) they are extremely slimy, and if you touch them bare-handed, be aware that their slime will NOT go off easily, even if you wash yourself. (2) They are the "knot masters". They can make knots on your line by twisting their bodies that even the most skilled fisherman can't make. It's a pain to untie the knots, and usually the person just cuts that portion of the line. Well...I do have to say that I hate to fish for them as well. However, they do serve as a very good bait for catfish - second best bait I would use for it (I'm not telling what the first is =D). I ended the session with 17 eels, all caught on nightcrawlers - bottom and still fishing with a 1oz weight and a size 10 hook, no further than 2 feet from where I stood.