Van brought up two powerful concepts of entering and turning. These are meta-concepts that are practiced in terms of physical conflict, but radiate outwards.
There are a number of advantages to this specific concept...one of them, that I think most people miss, is the tactical concept of using your space as an available weapon...i.e., 'conditional weapons' you seize upon and the 'deliver them' to the assailant.
Think of what's around us at any given time...a hard floor, a parked car, a lamp post, tree, a wall, stairs, etc.
The entering and turning concept is for those times when you really need to 'project' your assailant into a 'background weapon' such as catapulting his body weight momentum into a wall/car/etc.
The reason why at our dojo I have lots of drills with the defender against the wall being attacked, such as at a party, night club/etc.
Your job is to develop the abilities of 'tenshin swirling' _placing yourself mostly to the rear of the attacker, then using your centrifugal force to 'deliver the wall' to the head of the attacker...then follow up from a safe position in any action you deem appropriate.
This was used by one of my students when attacked in a rest room by a big obnoxious drunk.
He was busy taking a leak...when the drunk shoved him from behind and said 'Are you done yet?' Just imagine you in that position, in a crowded rest room with a line of people behind you waiting to take your place at the pisser.
My student did what I taught him to do...he spun around in a Sanchin turn on his left foot, then took a wide circling step around with his right leg while grabbing the drunk's left arm from his left shoulder...he then brought his left leg forcefully behind his right in a spin, and drove the drunk into the wall first, then showed his head into the urinal...and quickly left the area.
The perfect ending...no need to exchange blows at close range and or bodily fluids with that douchebag behind him. The wall, the weapon, was delivered to the target.
Amazing how many Uechi people don't get this point.