Well I suppose that the breakdown by party would be helpful to party leaderships in informing them of the general sentiment among their supporters. The reason I raised it was in order to counter the oft-made claim that most Labour-held seats ("in Labour's working class northern heartlands," etc) voted leave. Statistically correct, but if you say it, whilst neglecting to say that most Labour voters in those constituencies voted remain, you're being a bit of a scoundrel, aren't you?