I had a Blue Ox hitch too when I was towing my 35 foot Keystone Bullet with a Yukon XL Denali. It seemed like I made steering corrections all the time and it was a chore to tow more than an hour. I was within the towing limits of my Yukon as I thought my weights were off. Used a local scale to confirm it too. Had about 13% on the hitch. But after a 3 hour white knuckle trip last summer in 40 mph cross winds, I knew a change had to be made. It was either new truck or new hitch.
I discovered the Hensley Arrow soon after and my sway issues became a memory. This hitch truly eliminates all sway and lateral movement on the hitch ball. It does NOT use friction or torqued tension from the spring bars like the Blue OX or Equalizer hitches. It uses a series of cams and struts to lock out the hitch ball. Lateral forces applied to the trailer or TV no longer induce sway. The entire rig may 'nudge' slightly when being passes by a semi or when experiencing a crosswind. But there is no steering correction needed. You just drive 1 handed (even 1 finger) without looking back at the trailer. My Yukon Denali loved this hitch.
The issue I had was with payload. The Hensley chipped away at my Yukon's capacity by being 100 lbs heavier than the Blue Ox. Even though I travelled very light and was within specs, I didn't not have any reserve with payload. My kids wanted to bring more toys, I wanted to bring a generator, and the wife wanted to pack more camping essentials. This required to change out TVs. I found an awesome deal in May on a 2017 Ram 2500 Laramie megacab 6.4L demo truck with only 3,000 miles on the clock. I could not pass it up.
I never sold my Blue Ox hitch. It was still sitting in the garage. So for kicks and giggles, I installed the Blue OX on my Ram to tow my Bullet on our first camping trip this year. Results? Same as towing the trailer with my half ton Yukon. Constant steering corrections required at highway speeds. The corrections weren't extreme but my now 3/4 ton truck brought back memories of towing with my Yukon. The two days I drove my RAM towing didn't see much crosswinds either. It, just, was not a relaxing drive.
So, my conclusion: An inadequate pairing of a sway control hitch to a lengthy trailer. The Blue Ox may be a great hitch for much shorter and lighter trailers. But when it comes to coaches longer than 26 feet, the mechanics of sway control needs to be left to premium "sway elimination" hitches like a Hensley or Propride.
YMMV.