Jinnah expressed support for a lot of proposals so long as it weakens India, when Baluchistan petitioned India to join the union of India instead of Pakistan he was quite prompt in sending in the Armed Forces to remove the Kalat of Baluchistan while he condemned the Armed Forces Operations of the Indian army against the nizam of Hyderabad so saying Jinnah supported the idea is not enough
Plus the dominant community of Bengal were the Hindu sen community and other Hindu banker merchant community plus the Hindu landlords who were quite pro British or pro India, when lord curzon divided Bengal in 1905 along religious lines quite few of these elites supported the idea so I don't know how a few Muslim elite would stop the wish of Hindu Bengali elite who had desires to spread their influence through out east India after independence and for a time were quite successful at it Until the communist party took over Bengal in 1969 when the brief period of industrialization came to a crashing halt
As for burma I have to agree with
@Noscoper and I have nothing more to add.