@CardSharp
That is not my understanding. Several states have been re-organised; a quick summary follows. The great work of consolidation was undertaken by a team consisting of Sardar Vallabhbhai Patel and a civil servant called V. P. Menon, who wrote up the process in a tome called "The Re-organisation of the Indian States". Sardar Patel (Sardar is an honorific found on both sides of the India-Pakistan border, which approximately connotes a tribal or rural leader of some stature; by courtesy, it extends to all Sikhs - Patel was not a Sikh - who are typically Sardar Ajit Singh Majithia. On some other occasion, I will explain how to parse that name) was reputed to be a very strong leader, the strong fundamental on whose strength Nehru found the freedom to waft around the globe faffing on subjects that caught his fancy, including his patronising, condescending behaviour towards Mao Zedong and Zhu Enlai. Patel welded the vast number of Indian princely states that opted for India (the majority out of 562) into informal, temporary groupings, for instance, PEPSU, the Patiala and East Punjab States Union, which included the major state of Patiala and some other smaller tracts besides. The map of India from 47 to 56 was quite curious; like a map of gerrymandered political constituencies.
In 1956, there was a re-organisation and states were structured by language. The big concessions were the carving out Andhra Pradesh, which a Bangladeshi chucklehead habitually confuses with Arunachal Pradesh, from Madras, making Andhra Pradesh the repository of Telugu as well the successor state of the princely Hyderabad, and making Madras a Tamil province; and the carving out of Gujarat from Bombay, leaving Maharashtra to promote the Maratha language.
In later years, at no concerted point of time, really, some small configurations were promoted to full-fledged states, and several states were separated out. For instance, Uttaranchal out of the hilly bits of Uttar Pradesh; Bihar being split into two, Bihar and the largely forested Jharkhand (scrubland); Madhya Pradesh had Chhatisgarh carved out. Notably, Jharkhand and Chhatisgarh represent the forests with forest-dwelling tribals with major grievances against the regular settlers who come in and rip them off.
Now, can they take on a life of their own from that point onwards? No, as you saw in the case of the linguistic re-organisation, these states can be carved up with or without their consent. All three that I mentioned before, UP, Bihar, MP were states formed in 56, more or less.
More or less true.