Unfortunately Dietz’s article is behind a paywall.
I am fairly sure that the old April meeting at Aintree had more Flat racing than jumps, despite the Grand National being the main event. The old BBC commentaries used to refer to the Grand National runners crossing over the Melling Road and ‘back onto the racecourse”.
Chester and Haydock draw large amounts of people from Liverpool in the summer, so Flat racing does appeal in the locality. Would a third Flat course in the area be too much? 