If you do conduct the approach in VMC then I don't imagine it would count as technically being an instrument approach operation unless you had the hood on but then again in real life you would rarely have hard IMC right down to minima anyway. Could it perhaps have to be an IFR flight to count as instrument approach operation?
If only part 61 listed a definition for instrument approach operation. I imagine if there were it would be listed as something like: Instrument approach operation: an approach conducted by an aircraft flying under the IFR with reference to instruments. (Since VFR flights are limited to visual approaches only?)