[quote=@Gun]
[@yoshua171]Well, retroactive means retroactive in the sense that its used lol. By that, I mean while actions may be occurring simultaneously, by interrupting and stopping an action from ever having occurred when it was stated previously as currently happening, then you have, quite literally, time travelled, or at least manipulates it grossly. Actions have been entirely removed from the timeline, and is therefore 'retroactive'.

Hope this helps.
[/quote]

Most people don't use interrupts to prevent past actions, therefore future actions; they are mainly used to stop future actions by stopping them in between. The only person I've actually even seen try to stop them after they've happened was Khandy, who even had an ability specifically for that. 

Most, however, use it in a manner of thus:

Person A runs towards person B, utilizing two diagonal slashes, and then a backwards spin slash, thing.

Person B can interrupt at several points here, actually, depending on the time scale of Person A's ability

1) Person B moves as Person A does, meeting them just before they execute their two slashes, and aiming a cut of his own towards their sternum. This cancels both slashes, and the last slash... thing.

2) Person B deftly dodges the first slash, and cuts towards Person A, as they are raising their blade to continue with the second slash. This cancels out the final two attacks.

3) Person B, after guarding against the two diagonal slashes, bumrushs Person A as they spin for their backwards slash, aiming to slam a shoulder into their back. This ends their last attempt.

Neither one goes back in time, they all just do the logical thing. If you would, could you provide an instance of an illogical interrupt? From what I'm reading, your issue is less with interrupts, than people who are time weavers. xD