The anime is not canon. It's clear in the manga that the technique known as Parasite works by attaching a string to the spine. What Doflamingo did in chapter 790 is not the same technique.
In regards of what Doflamingo used to control the movement of characters before the time-skip, it appears to have been Parasite, given the characteristics:
- Nobody was able to escape the effects of it, including Diamond Jozu;
- Doesn't seems to have a limit on the number of individuals it can manipulate simultaneously;
- The effects vanished with time;
Also note that in chapter 790 Luffy is in an open environment, wouldn't the strings get enrolled if he used it like that amidst a war?
Everything in the Anime is not always non-cannon, is the Red-Hawk we see in the Anime non-cannon? the Radio knife non-cannon? The Anime needs to be consistent with the manga. I can understand the stories not being cannon, but now techniques too are not cannon? Makes no sense to me anyway.
Also, can you prove that Parasite is actually just a thread attatched to the spine? Where in the manga is it stated or what panel can you show that proves this?
How can you distinguis that this is not Parasite?
It contradicts what we saw at chapter 790, initially we see Luffy is not moving and we know it's Parasite, as soon as he uses Gear 4th all these strings become visible and snap and suddenly this can't be Parasite? Who else has broken out of Parasite in order to conclude that it can't be Parasite?
It really is the only technique Joker uses to bind people, so that's unequivocally Parasite. Until we see Joker use parasite and someone decides to shrug off the effects simply by pulling a string out of their spine, it's speculation that's been proved wrong and has no basis any more.
When Sanji got caught by Joker, we all assumed it was Parasite because he stopped moving, we never said must be a different technique. When Joker used Parasite on Jozu, he stopped moving similar as other character that have been victim to this technique.
Lastly, Jozu is not a standard by any means, just because he's a Whitebeard Pirate doesn't make him untouchable. Jozu got frozen by Aokiji and lost a limb and was rendered completely incapacitated while Joker shrugged it off, but with a significant show of effort applied. He's overrated, Luffy escaped Parasite whilst Jozu didn't.