The chinese loop has got everything to do with the rubber itself. Here's the thing, with chinese rubber, when you're close to the table, u can hit early, overcome spin and create your speed better (flatter contact). But when you're far from the table, you don't create speed, but in stead, you brush more to create more spin.
Contradicting to the Euro/Jap rubbers, when you're closed to the table, you don't hit hard (it's very bouncy), but u create friction to create spin. But when you're far from the table, you don't create friction, you create speed.
So there! you can see it clearly, that the chinese way of loop with their rubbers is really a science itself.
Let's give you an example:
A serves underspin to B
B pushes back
A got 2 choices (if using chinese rubbers) : 1- Hit with closed bat angle and create lightning speed, 2- slow loop to create spin (rarely happens)
A got 1 choice (if using Euro/Jap rubbers): 1- Brush the ball as hard as they could to create spin. (this is where Timo's loops get killed alot by the Chinese)
When this happens, Chinese looped ball will be harder to counter, hard to block, hard to punch block. While Euro/Jap way will be easily countered with above mentioned methods.
Another benefits of the Chinese loop, i see very clearly is the straightened arm when they loop. See, with your arm straightened, it's easier for you to loop when the ball is 30 cm, 50 cm, 70 cm even 1 meter ABOVE the table surface level. You can refer to Ma Long's loop when the ball is really high.
The benefit of Euro/Jap loop is the ability to affect right top spin, and left top spin on the top-spin incoming ball when it drops near table surface level (see Timo's). But when the ball gets higher, it's become harder to execute more force and spin on the ball.
If there is anything that makes the Chinese reign TT for the past 20 years, it must've been the Chinese way of looping. And trust me, if you're are 1m85 or taller, please forget this way of looping, your physical condition just don't approve this technique.
By the way, i'm not Chinese. Cheers