Yes, KA on MG Reds vs. X30 on MG Yellows have very similar braking points.
Threshold braking = braking at the very limit, just before locking up, so you’re getting maximum stopping traction. The tires should just chirp slightly.
Trail braking = carrying braking application into the turn-in point of the corner, sometimes up until apex.
So you’re seeing me do both. I brake hard and get the kart slowed down quickly, but I’m braking at the maximum latest point so I’m carrying a little brake to the apex usually. This means there is minimal coasting, and I’m almost instantly back to the throttle as soon a I come off the brake. Some drivers don’t trail brake as much, and they get the kart slowed down a little sooner and are able to get on the gas a little sooner. I’ve found that because of my height, trail braking helps me load the kart onto it’s nose a bit better, and transfers the weight better since I don’t have a high center of gravity. A taller driver might not be able to get away with trail braking because they’ll overload the kart with their higher center of gravity.