I don't think low dynamic compression can be used as a reason to run low octane fuel UNLESS you are going to keep the engine speed low.

As soon as the engine comes up on the cam then the DCR goes out the window and you are running on actual compression ratio. That is why race engines with huge cams still need to run race gas. They might not need race gas when driving around in the pits but they need it as soon as they go WOT down the track.