That tension between adventure and safety is what makes “Titanic” more than just a collection of tragic sketches. Perhaps a little baldly — Yeston’s lyrics are not as sophisticated as his music — he has Andrews (Jose Llana) say, in the show’s first words, that the liner he designed is part of mankind’s eternal attempt to “fabricate great works at once magnificent and impossible.” It’s a statement of hubris, of course: The show, after all, is about the human urge to dominate nature — and other humans — by whatever means necessary. Yet in art we can’t help relishing that hubris, if works like “Titanic” are the result.