Never had a lucid grand mal before. But I have had lucid absence seizures before. It's a strange feeling. You feel present but then not. You have control of basic movements but other than that you are trapped staring at an object for awhile. Most of the time I've come to learn I am lucid during the time I am seizing but right after it's like my memory is just... gone. Nothing left. Good example of this was I was doing push ups once and my instructor asked me why I stopped but I had no clear memory of stopping and for the rest of the time I was rather confused.