Well, usually the whole shitshow starts when something like a tensioner guide fails. I've seen a couple lately where one of the boltsbreak off in the block and the guide is just flopping around and valves are hitting pistons. So thats how it starts, then some guy "fixes" it but doesn't get the valve timing right. Most times you get the cam crank corolation faults right away on startup. But there are those few that sneak by with that exhaust cam advanced. I have no idea why the cars I've seen like that had no corolation faults. It's probably about plausability. Why monitor for something thats not mechanically possible.
When I've seen that cam timing problem I would describe the idle the car had as busy. it wasn't smooth, but it didnt feel like it was dropping a cylinder. It just wasn't a normal idle. I watched the misfire counters and they all just incrimented up slowly on that bank untill the ECU turned off the injectors. Once that happened the reduced power message comes on and a key cycle would bring it back for a while. Good times.