> Where as usually my notebook cells are only a few lines long, and with a very clear state going in. That is only true in one very specific case: When you are

> Where as usually my notebook cells are only a few lines long, and with a very clear state going in. That is only true in one very specific case: When you are executing all code cells in order, from top to bottom, exactly once. If you start executing cells multiple times, or out of order, or even worse, execute only parts of cells (which is possibke in many Jupyter UIs), all bets are off. Anything can happen.