I would say yes.
For starters runflats are heavier tyres then normal ones, so the rotational mass would be reduced, therefore less energy needed to actually move the tyre leaving more energy to be transferred to the road. Also now that you'll have less undampened mass the suspension would work better so more chance of keeping the tyres efficiently on the tarmac will leads to better grip. Finally as the range of non-runflats is far greater then the runflats, you 'll be able to get more grippy rubber.
I'm sure there are many more reasons...