@Rilla Thanks for still trying to get a grasp on everything here. Now onto your inquiry. I've experienced both time weavers and serial interrupters, and I dislike them both equally, but my primary issue with most interruptions I've come across are that they are used handwavy as hell, almost as a way to 'legally' timeline, and get away with it.
Your scenarios are not interrupts insofar as the definition I gave them when they are used illegally(retroactive prevention of an opponents actions), your scenarios are entirely fine by me, actually. I'm pretty sure I said earlier that simultaneous actions don't count as 'interrupts' to me. As in, I swing my sword twice(or at least attempt to) and you clash with my first strike, that's just simple action and reaction.
So essentially, I hate it when people take interrupts to such an extreme that they are essentially time traveling, and that's majority of what I encounter. A recent example was over on Valucre where I created a vacuum, and then I believe something involving fire thrown at the enemy. The enemy then used my vacuum oh-so-cleverly to cause an explosion at point-blank range, completely nullifying the second half of my actions(fire junk). My fire never became an issue, because it never happened, because he stopped it from happening, though he also stood by the 'i iz not gunna watch you do junk. Das stewpid!' when my action was both unprepped, and fast as hell, and all the judges shared his opinion. You see in your scenario, the guy didn't prevent the sword strike from happening, he just... Actually dealt with it lol.
Note: It should be stated that when in cqc situations, my idea of interrupts is a bit more lax, because of the nature of cqc itself. Most times people aren't just going to do a literal single punch or kick, because fights would last hours lol. So doing things like 'interrupting' some dudes 30 punch barrage is also fine with me. But doing something like 'as soon as his arm flexed, I punched first.' thereby changing everything, isn't. And that right there? The whole 'reflexes' excuse to get away with it is the most general reason given.
'I have fast reflexes, so I see you about to move, and instead of preparing and reacting accordingly, I'm gonna argue that my speed and reflexes together would make my interrupt entirely ok and logical.' not that there isn't a defense for that, but I just find that its majorly used as a way to sneak out of unfavorable situations, at least when they were fighting me.
'man, that attack is kinda deadly and I don't really got too many answers for it. OH. I KNOW. ILL JUST STOP IT FROM HAPPENING.'