Evan, in the late 1940's when Perfect Circle came up with the idea that worn piston skirts could be knurled to minimize piston slap during an overhaul, they intentionally tried to over-knurl a set of pistons to see if somebody could damage an engine that way. They built up a flathead Plymouth engine and knurled the piston skirts to .005" over the bore size. They had to drive the pistons into the cylinders with a big hammer and a block of white oak, and the starter wouldn't begin to turn the engine over.
They filled the trunk with sandbags for traction and got the engine started by shoving the car down the block with the push bar on a big wrecker. It took full throttle in first gear for a few miles to keep the engine running. Eventually things loosened up enough to shift to second, and then third. They were a long way from their research shop when the gas tank ran low, and they had to shut the engine off to fill the tank. The starter cranked the engine properly, they drove back to the shop, and one of their researchers put several thousand miles on the car before they tore it down for an inspection. No ill effects whatsoever from the over-knurling. I still knurl pistons occasionally, and it still works!
Jerry
