as it is - 'returning to neutral'.....where she would have the ability to play either fh or bh - depending on the answer from the opponent

pretty good, actually

:)

Actually what she does (and almost all of the pros with good technique do) is that she accelerates slightly before contact but mostly during contact, and after the contact is made she lets immediately loose making it look like she is "stopping" the movement. 

In the first FH loop I think she does stops the follow through a bit by not jumping away from the ground in order to be fast in good position for the next shot.

I think she wants to add as much spin possible in the 1st loop but without losing any time to recover for the next shot. If she let completely loose after contact her body would jump a bit as the whole motion is upwards.

For me its definetely not a technical flaw, rather it shows the level of Ariel in handling shots like that with consistency. 

A view of the other player would give us more information.

Seeing the video a few times again I believe that her first loop is purposedly landing as close to the net as possible (perhaps her opponent cannot cover all of the table effectively and is maybe a bit far)  thats why you see mostly upwards motion in the first loop and almost none forward motion. The next block (or chop? the trajectory tells me it is block/topspin shot most likely) is bad and bouncy, resulting in a fast attack, the opponent struggles to bring it back and ariels smashes it

So judging from what I see and without knowing the exact position of the opponent, my guess is that the first incoming ball is easy for Ariel to handle (12-18 cm over the net). 

Such a high ball gives Ariel the advantage of choices 1)loop hard and long near the endline of the opponent 2) Loop by accelerating only in an upwards motion using the minimal power needed for the ball to pass the net safely, keeping the opponent pinned-> bad block/chop -> easy ball for ariel who smashes afterwards

Now my english are not so good to explain 100% what im trying to say but I hope you get the point. I will use an example to make it more crystal clear.

If u throw a semihigh ball to your opponent and you see him stepping firmly to their right leg, falling their playing arm and waist under the table, you must take a neutral position over the table (both vertical and horizontal) in order to cover all angles in case the ball comes fast. 

This is the worst case scenario, but again the opponent can change direction at the exact moment of contact giving you a slow spinny ball as ariel does, if you dont have perfect position to countertopspin the ball, whatever stroke you do it will not be effective. Same thing happens in the video 

Again this is all a theoretical assumption of mine, as we dont know the exact position of Ariel's opponent. Ending her technique is very good without flaws in my opinion, maybe she could add more spin with wrist snapping in the 2nd loop but then again its obvious she chooses speed and placement (the 2nd loop goes diagonal) over spin, in order to take her opponent out of position as she actually does if we judge from the last very high ball that she smashes.

Another thing I noticed is that, if you see the video in 0.25 of its current speed, ariel does not know where the 2nd ball is gonna come she turns he paddle for BH to cover it and then immediately changes to FH when she realizes its an easy FH ball. That tells me that her opponent probably is in the same line with the middle line of the table maybe a bit to the BH judging from Ariel's glance to the ball after her 1st loop.

If we had the whole picture along with the opponent's position, its a perfect example for beginners to show how to take advantage of high balls, keep your opponent guessing the placement of the next ball and finally building up the point safely untill u can finish it with ease, instead of hard looping/smashing the 1st semihigh ball which can sometimes come back to you real fast by a block off the bounce.

Some of my thoughts exactly, but you made it much simpler :P

I am not saying that LXX isn't better or more efficient just that they are both having to manage the same type of inertia and so have similar motions at the end of their strokes in order to recover.. 

The take backs start close enough to the same place there really isn't that much difference in terms of the starting position. It's a little harder to determine where AH's take back is because of the camera angle as well, but I have seen her live and she does take her arm back a fair amount on her opening loop against underspin.   The stroke angles are a little different as well, AH more vertical than LXX . Also LXX show more upper torso turn during the follow though. 

For her type of stroke mechanic and the intensity of the shot I don't think that the recovery motion is abnormal.

LXX is bigger for women so she might go for more powerful shots. but everyone does that some time. ariel just specializes in quick attack so you don't see her using motions for big loops most of the time. 

https://www.youtube.com/watch?v=53pZqN4VLn4

I dont see any additional acceleration after contact has been made. If you want to somehow "stop" the follow through you do it because you wanna come back to you ready/neutral position faster, not because you can emphasize with  spin by "arresting" your swing.

KK is away from the table so he could try harder/longer swings if he wanted to, when u put pressure on a defender u have plenty of time to come back to neutral position, KK's example is a different thing from ariel's, although their strokes look similar they are not. 

KK in certain occasions loses contact with the ground after a shot, and ariel doesnt. 

I hope you are not comparing these two to reach a safe general conclusion, cause different situations handled by different players, require different/unique strategy and technique

Who is "trying"? What does XX has to do with the whole topic?

1. I dont "describe" it as a snap, it is a snap :)

2.Try to accelerate during contact and then "Arrest" the motion, you will find it inefficient to do so. Then try to accelerate during contact and let your muscles loose after contact. 

Play 20 FH topspins  against block  (middle to FH for example) over the table. First try with "arrest" motion and then do it by letting loose. Which way is more efficient?

There is no additional acceleration in the 1st loop, but it is in the 2nd because she wants to get her opponent out of position fast, so she adds some extra power. 

1st and 2nd loop are quite different occasions, you cant say that Ariel is using the exact same technique on both of them

First loop is against backspin, 2nd loop is against topspin or nospin/light topspin

Υes I understood that the whole "arrest" issue is refering to the follow through not the acceleration during contact, I never said the opposite so we agree on that :)

I think every player with deep understanding of technique, does not matter if you are ZJK ML or not, tries harder to lift an underspin ball against a defender with brush loop thus tensing his muscles more during contact.

Against a non defender, attacker/blocker countertopspin player you dont have the luxury of attacking too hard or brushing too hard with a huge motion jumping off the ground because the ball might get back very fast on you. 

Besides against topspin/sidespin/no spin balls from a non defender you dont have the time to get back on position (after a hard brush loop) so the most effective way is to drive loop with relaxed muscles. Or you can examine your choices some how like below

1.Drive loop very hard like Ryu or ma lin and risk getting the ball back at you with a block and you are out of position or win the point because the loop was too good for the opponent to counter.

2.Drive loop with shorter and relaxed motion and be ready quickly for the next shot, cornering/pressuring your opponent step by step untill you can finally smash the ball or finish the point at any way available

I think there is no general rule about the snap/arrest issue, you will "snap" and "arrest" differently against a blocker/countertopspin player and different against a chopper. 

I believe that when you play a point the ball somehow "talks" to you. Some balls are to be smashed with whole body,others to be loopdrived,others to be brushlooped with whole body,others to be brushlooped only with the arm and waist (like the semilong underspin balls which fall near the endline of the table) 

There are countless possible balls and countless possible ways to counter them :)