My Cub came with very high tongue weight. It probably did not need sway control because of the high tongue weight. Gross trailer weight is spec'ed at 4400#. Tongue weight loaded for travel was 950#. Minimum 10% required would be 440# tongue weight. So, double weight needed for stability.
I bought an Anderson WDH with the TT. The WDH has built in friction clutch sway control. I have never had the slightest hint of sway. I had to modify the front "A" frame to reinforce the WDH mounting points for use with the Anderson.
I posted the mods in another post if you are interested.
I wish you good luck and happy trails ahead!