5.7 has the sniffles

In the first two weeks, the miss would show up, and turning off the engine and restarting made the idle damn near perfect.
This was 100% of the time, so it was sitting in one spot, I think and if didn't fall exactly in line with the built up carbon it didn't seal well. It could be a wiped lobe, but I wouldn't expect that to be a variable condition.
I've read about bringing the piston up on the compression stroke, pulling a plug, filling the chamber with Sea Foam and letting it stand overnight.