a few thoughts:

1) UA isn't closing CLE anytime soon, despite the constant rhetoric, CLE is a very profitable operation for them. There's no downside to having a 'hub' unless you're losing money on the flying. They do get a lot of upside, with the corporate contracts and hub pricing.

2) IAD has been 'right' sized to the CO mentality. CO doesn't run widebodies domestically. so all those flights are gone, and would've been either way. When it was UA, IAD was a highly lopsided operation, it was either RJs or widebodies, with a low % of narrowbodies relative to the other hubs.