KITT spins his wheels into the sand. In the next shot, the wheels are on top of the sand as if nothing happened.
As Michael maneuvers kit away from the hovercraft's rockets, there is grey "patch" visible above the right rear wheel. After the hovercraft turns to head for the water, we see the right side of KITT and the grey patch is gone.
At the pier, KITT comes to a stop to turn off Super Pursuit Mode. Just before driving off, KITT's front end and hood are out of alignment. They're straight from then on.
When the thieves were starting up the hovercraft the sound is that of a Rolls Royce RR250 turbine helicopter engine, but when the malfunction was occurring the sound was that of a sputtering piston engine.
Near the end of the episode, when Michael and KITT face off with the hovercraft, explosive "squibs" are visible on the hood and side of KITT right after the rocket explodes on KITT's windshield. The squibs are used for the gunfire that follows.
A pincer trap is not a military term. He probably meant pincer movement however the plan he set up was nothing more than a simple ambush. A pincer movement involves two armies outflanking the defenders in the middle and creating an encirclement.