Building a trebuchet from scratch and finding the best proportions, weights, angles etc by trial and error certainly works ..well, that's how the Grey Co's first machines were done... but if you could model the rock-throwing beasts mathematically then think of the work and possibly wasted effort you could save.
"Think of the ocean as our global savings account -- and right now, we're only making withdrawals, not deposits. Enric Sala shows how we can replenish our account through no-take marine reserves, with powerful ecological and economic benefits."