There is an article in Anglers Mail this week by Steve Collett about how he won a European lure fishing contest on the Gloucester Canal by catching 88 perch, mostly small with one 2 pounder. The contest was decided by length rather than weight, so it's clear why catching a lot of small fish was the right strategy. He used very small lures, and caught a lot of the fish close to the near bank, jigging under the rod tip.
A point which surprised me was that he lowers the lure in slowly, a foot at a time, to see what height the fish are at. He rarely catches perch on the bottom, and when he does find them there he has a very light jig head so that the lure drops slowly. The last point doesn't surprise me. Under Kappa's guidance I know that perch often take on the drop.
But the bit about lowering the lure slowly, a foot at a time, was more of a surprise. The few times I've tried it didn't work. And I've mostly caught within a foot of the bottom. I'd be interested to hear other's experience.