Doesn't the HST have a cruise control function to maintain the travel speed freeing your foot up to operate the directional braking?
They're also really nice while traveling the side of a hill sideways. The upper wheel always tries to travel a little faster than the lower wheel forcing the front to slide downhill some requiring you to countersteer and can lead to a total loss of traction easier than if you simply press the brake for the uphill side to slow the rotation of that tire; the front no longer tries to slide down the hill and no countersteer is required.