Maybe I'm not following your thinking very well.
Submersible pumps are meant to be underwater. And why would you want to remove it during heavy rains? That's when you need it most because if you think the water level is going to stop a couple inches before overflowing the pit (regardless what the other pit does), you may wake up to a basement floor covered with a few inches or feet of water.
Sump pits and pumps are meant to be used to prevent foundation and other water caused problems with the building. Specifically cellar wall foundation footers.
So your choices are to save the electric bill or not and potentially ruin the foundation or at least to not have water all over the basement floor and up inside block cellar walls.... which do you suppose might cost more in the end?