Then the only explanation for that is not scientific; you have tearing but just don't notice it, which isn't unusual especially at lower frame rates where imperfect motion clarity can obscure the tearing somewhat.
Strobing won't cause stutters, and like I said it has nothing to do with tearing so the same rules apply. If you play games windowed/borderless windowed, then you won't see tearing. Perhaps that explains your experience.
Strobing usually adds some amount of input lag, but these days it is not even detectable to anyone. Otherwise yes, strobing has no impact on tearing so the same principles apply; FPS and refresh rate need to be synced in order to avoid tearing.