King's "Status Promotion" amplifies certain things. Merlin stated that King mainly used it on the forest's trees in order to "amplify" the rate of their growth, hence giving life to the forest.
I guess so. He could increase the rate of thrombocytes to close a wound or something close to it.
He can probably accelerate healing but accelerate age should be impossible.
Well, king can turn light poisons into deadly poisons and turn tumors into larger tumors... And we did see him trigger rheumatism. And one of his spear forms has the power to fossilize things. King seems to have dominion over natural processes. He can enhance them so to speak. So it wouldn't be that much of a stretch that he can increase or slow down aging and maybe even revert it. The issue would be that each of this things would be greatly limited. So he probably can do all this stuff but it would be greatly limited. Much like his status promotion, its not like he can turn a light wound into a wound large enough that meliodas ends up split in two.
But can't he use his abilities repeatedly so that the effects stack?
I don't know, all we can say is that we have not seen hims stack the effects of his ability. King did try to use status promotion again but he was not necessarily targeting the wound he had already opened. Meliodas had two scratches after all, the one on his face and the one on his shoulder. Then again the second status promotion did seem to fail due to mel's full counter and king did feel pain over his shoulder. Of course, if king can really just stack that technique in many ways its more dangerous than most of his other techniques, even the ones that seem to combine chastiefol and disaster.
Why do you guys associate Status Promotion with the worsening of a wound? King might very well have a disorder which prevents his wings from growing, which may imply that King's "inverted" wings' growth was triggered by the countered Status Promotion.
We have yet to see whether status promotion has positive results. For all we know king has an entirely different technique which allows him "positive results". How would positive results even work in this context? How would king make someone healthier so to speak? It wouldn't work on someone who is already healthy. Unless king can make people more fit or something.
King was said to have used Status Promotion to amplify the growth of trees in the Fairy King's forest; how is that not positive?
No one said king specifically uses status promotion to do that. Merlin said king uses disaster to rule over life and death. Status promotion is but a single technique within disaster.
She stated that Disaster's abilities include amplifying certain things and went on to associate this with the growing of trees.
Regardless of the translation merlin was talking about disaster in general. Her description of disaster does not necessarily mean status promotion is the specific technique king uses to do all the things merlin talked about.
She referred to Status Promotion as Disaster; nothing more, nothing less. She clearly went on to explain its effects and did not deviate from Status Promotion.
Who said there's only Status Promotion to Disaster?
She clearly said it was his "Original magical power"
Original magic power does not necessarily imply he had others. The issue here is that king's situation is murky to begin with as he has multiple power sources so to speak. King as a fairy fights in two specific ways, he draws out power of the sacred tree (in his case through chastiefol) and he has his own ability, disaster. And it can be hard to tell when each one starts. King has had more fights than most sins and even only recently we got to see disaster in action and some context as to what it does. His fighting style is completely different from anyone else due to how he supposedly uses his power (he uses his disaster to draw out the qualities of the tree).
You're speculating that she gave only one example of Status Promotion and went on to the general ability of Disaster, which is unlikely judging by the context.