Just came across another instance of Stanley Wolpert's creative approach to writing history. In chapter 8 of "Jinnah of Pakistan", Wolpert writes:
Long version:
On February 12 {1928}, Jinnah attended the All-Parties Conference chaired by Congress president Ansari in Delhi. Motilal and Jawaharlal were there, as were Lajpat Rai, Malaviya, Jayakar, and most of the other leaders of political India. Gandhi did not attend; he remained at his Sabarmati ashram, placing as he did so little faith in constitutional planning.Short version: Wolpert is wrong in why Gandhi did not attend.
Long version: