there are two prominent bugs that appear when a hog is sliding (or rolling, which I imagine is the same thing).
first off, sliding can be immediately stopped if you activate a rope (or maybe other weapons too). This looks rather unrealistic, for if a hog is sliding quite fast, it will stop on a dime when it uses the rope. It also creates a rather nasty bug, in that if you activate a rope right next to a wall, you won't bounce off it, but will stick to it. This will of course lead to either falling on the ground, or if you have enough time, aiming the rope at almost a 90 degree angle in order to stop yourself from falling.
the other bug with sliding also involves fire. If we take the hellish grenade for instance, once it explodes, a hog will usually start rolling on the ground. Even if the ground itself is on fire however, the hog will not take any damage from it as long as it is rolling, which in itself can take a long time, thus diminishing the possible damage.