To answer your question straight forward, yes. Typically there would be a gain in power with advancement in timing. However under "normal" ignition timing there will be less of a chance of pre-detonation. Compression ratios are important here as well. On higher compression engines (9:5.1+) flame front changes. Also is the factor of intake air temperatures related to oxygen densities thus altering burn rate of any fuel and changing cylinder temperatures. It is a "safer" bet with todays fuel mapping on most any ECM vehicle to venture with higher octane under a lean burn condition. Especially on lower compression engines. However the benefits in power are nominal to non in low compression engines. There are many factors that may and can change the "state" of a fuel, some more radically than others, all that will effect the burning of the fuel and it's work force in the cylindar.
Yes to Direct Port Injection or Direct Fuel injection. To those around me we use DPI. Realizing there is a difference in terminology DFI is more common under what I'm referring to. Primarily fuel injected into the combustion chamber other than from behind the intake valve. Here is a good paper from MIT
http://www.ethanolboost.com/LFEE%202008-01%20RP.pdf Also Dr. John Heywood has patents related and other papers related. The methodology is something similar to what we use but with a different "injection" system if you will.