Hmm, thus far I haven't notice a difference, but I've never really had an issue with the controls (which is saying a LOT, because I have control issues with most Wii titles). Perhaps it was the sensor bar, or you played during a sun shiny day.
And GP, its rather odd. I've owned LBP since launch and I have yet to release a level for the same reason. Considering I'm always writing music and playing in front of people, I figured I'd do the same with Smash, LBP, and Boom Blox. Funny how it goes. I guess it just boils down to the fact that it requires a lot of spare time to create and I'd rather spend that time playing someone else's creation.