No, it matters. It is not a high percentage, I can't recall the exact numbers, but it is significant.
It doesn't make overmolds 'better', but from a standpoint of physics, and flight, it matters.
If you dont think a spinning weight matters, look at the crazy amount of money bikers pay for a few grams weight reduction on their rims.
Now, perhaps your style doesn't jive well with needing higher angular velocity, thats cool man. There is a reason that there are so many different discs on the market.
Also, did not the orginal blizzard only have bubbles in the flight plate? From what i understand, Dave did that to increase the rim weight.
I am not an Innova hater like many, but I see Daves comments as nothing but sour grapes.