Actually I would be more leary of the partial egg than the clear egg but that is just me
I have hatched thousands of eggs, and I have never had a "started," egg explode. The exploding eggs I have had were rotten eggs.
This is good to know! What makes a rotten egg though?
Old eggs. For instance, found a nest of eggs. Unknown how long they have been there. Put them in the bator...... bad luck would be rotten eggs exploding.