The CT sits on 18″ rims, whereas the 2WD sit on 19″ rims. Other than the 1/2″ drop caused by the smaller rims, clearance is the same. I’d say generous clearance, no hang up issues (based on riding with a 2WD Gear-up).
I’ve never had an issue yet. I did the Molesworth in the pouring rain with no issues and had a go at Nevis road too. Made it about 6-7 km in before the deep water stopped me, not the ground clearance. Also better tyres would have helped, still had on my street tyres, lol! Lowest point is the mufflers at a hair over 7″ and I have not scraped them yet.