I'd say the perch I've been fishing for in the last ten seasons with light lure tactics (jig/dropshot ) are , by a huge margin, the least territorial fish I have ever encountered. Yesterday's hot spot is often today's blank , and that is why you need to keep on the move all the time to keep up. Ignore a lot of the tired old tut trotted out every week about targetting structures , weed , cover and lock gates. I have caught plenty of perch in such locations but I have done just the same on apparently featureless stretches of river and canal, and most of my bigger 'wild ' perch have come from almost entirely random spots . You can hit the jackpot where you expect to -I once had over 30 perch, most net jobs , from an area smaller than my bathroom below a lock but, guess what ? , I've never had more than a handful from there since .
From countless hours and many miles chasing them , all I'd say is target shallow water in deep rivers in the summer months and never stop exploring . It's nearly all about location - lure pattern is far less critical. Like fly fishing, the longer you have done it , the more you catch and the fewer patterns you need . Some spikey shads , some paddle tails and Z Man Ned Rig lures and you're good to go. Travel light , walk far and explore the less obvious swims- the fish don't read the magazines and internet connection is very poor subsurface so perch don't necessarily behave as people expect them to...
The only exception to the 'rule ' I have found is fishing commercials . I only fish a couple , and only in winter , often in vile weather with no anglers around and I have found definite hot spots, even in small lakes . The tricky bit is that they aren't features as such - so not islands , bushes , points or platforms but apparently random areas in open water.
Perch can feel like the proverbial mystery wrapped inside an enigma but the only thing which gets my heart beating as fast as a big perch is abig grayling .