JerryL makes some good points,but I disagree with his definition of "structure". I grew up with the explanation had only to do the bottom of the lake. (flat, dropoff, hump, depression, including man - made structures-bridge, rip rap). Cover is not structure. Cover would be weeds, stumps, docks,brushpile, tire, some old fridge etc. A leaning stump in a flat filled with vertical stumps is not "structure". I do agree that it's good to fish something where 2 different things abut each other (2 different weed types, chunk rock/gravel, etc.) but I could be wrong... I never tried his no-bo line, short stout rod,or trolled seriously, but I do still have his book and a couple of spoonplugs.