I think this reinforces the notion that ideas are fairly cheap; it's execution that matters.
But, going with that: Conversely, a better execution may be more difficult to implement successfully.
My original point was that the G-GP's statement was self-evident to the point of meaninglessness. You could flip the bits the other way and say something equally as meaning-ful(less).
Both idea and execution have some level of importance, but holding one constant while improving the other does nothing to discriminate between the relative value of either.
It's more humorous to consider maths and programs as ideas. And when I say humorous, I mean that very seriously.