Oleg Antanov, the famous and talented soviet era aircraft designer was wrestling with a power to weight ratio problem on one of his planes. To reduce weight he decided to replace the four stroke back up generator with a lighter two stroke version.However the guys in charge thought this was a great leap too far and commanded that he replace it with a three stroke engine and if that proved successful he could then progress on to the two stroke version.
I’m not sure why I felt the need to recount that true story right now.