Lower cost car insurance?

See http://www.bbc.co.uk/news/business-29339753 .  It looks like car insurances may drop in cost soon. I hope so, as insuring cars is an expensive business. In my own case I have to declare my brain bleed a year ago to my insurer as "a pre-existing condition".  I have no idea what difference this will make to how much I shall have to pay. Not too much I hope.