The law of diminishing marginal utility is at play in Mumbai politics. Shiv Sena, humbled by repeated negation from senior partner in the ruling alliance, is back to its old tricks. It is playing the thug in public view. This time, however, its black paint strategy has badly backfired. It is under all round flak including from BJP. Uddhav Thakceray and his supporters for sure have every right to protest, but the manner of protest here is regrettable. Apart from setting the stage for a split in the ruling alliance, the blackening episode shows how far removed the party leadership is from the general public mood. Shiv Sena can no longer sustain itself on mere nuisance value. It must reinvent itself to stay relevant in the ever changing socio-economic cultural milieu in India, so well articulated by the financial capital of India.