For future reference, I do not like this, as it seems to be something that would be the most effective troll bait. These things are kept to pm's for a reason.
In my post I stated, "As the red-head spiraled out from her Kamui portal Bel would use a simple wind release manipulation to blast the sand in front of him up into a temporary wall, blocking the woman’s line of sight to him. He would jump backwards, down the incline of the sand dune he was on, as he unfurled a scroll that hung from his waist."
Now it is not clear whether or not jumping back and opening the scroll is sequential or simultaneous with the first action. So if she had taken advantage of that lack of detail Machina would have been correct. However, though she expressed the idea to me in pm's, it was not translated properly into her post.
I used the fact that she did not state which Kamui she was using for each action to make her chain of events longer(claiming she used the right eye Kamui for herself and Tsuyo, therefor requiring her to complete the first before beginning the other), and I clarified my own actions, as nothing she posted actually contradicted anything of mine.
It isn't a retro post because the issue (whether the actions were simultaneous or not) was vague in my post, not addressed in hers, and thus I was able to correct it in my second post.
If I had gone, "Bel makes a wall, then he jumps back and then he unfurls a scroll." it would be a retro post to say it was then all happening at once. Or if I made the same first post that I did now and she actually noted "Machina releases Tsuyo via Kamui, which she is able to do before the time space barrier is up due to the small amount of time, raising the wall of sand, before Bel unfurls his scroll and activates the barrier." then I would also be incorrect and retro-posting. Since she didn't actually do that the detail was still up in the air, and I made sure to grab it.
As for what she is saying about changing her actions to then be using both Kamui's that is a retro-post, of course, because I did explicitly take advantage of the lack of details and note what is happening.