Three seasons and nothing to show for it beyond some mud-slinging and plenty of expensive rebuilds - McLaren-Honda's divorce was drawn out in full public view, with fundamental design flaws at the heart of the problem.
The humble oil tank seems such an innocuous component amid the extraordinary complexity of V6 Formula 1 engines and their hybrid parts. With all the millions of dollars invested in trying to make a success of a works grand prix operation, combined with the expertise of two mighty racing organisations, you wouldn't expect something so basic to be the root cause of calamity.
But that's exactly what happened in 2017. The unfeted oil tank is the chief reason why the McLaren-Honda alliance is no more, dissolved in a poisonous concoction of broken promises and shattered dreams.