Frenzy hit check

From my Frenzy play I think that the rsults of each weapon is calculated separately and the answer would be yes to both of your questions, but I have no proof. I went looking on other forums as I got curious because I used to play Frenzy barbs quite a bit. I found this discussion from 2009 about problems with Frenzy weapon speed calculators. I think it definitely answers your second question

since as TitanSeal pointed out the calculator is accurate for Frenzy's sequence length when the first attack in the sequence doesn't hit: it's only when the first attack hits that there can be a clear disparity between the lengths of the two attacks in the sequence, since the calculation changes (both in terms of WSM and weapon IAS used, if I understand correctly).
Having just done a quick test with 95% chance-to-hit against a monster with 75% block, it seems the calculator remains accurate if the hit-check of the first attack is successful but the hit is subsequently blocked, so it can be accurate more often than not against monsters with high block, like Diablo (50% block in Hell), or other players when duelling.
This could be quite tricky to incorporate into the calculator, unless you just had separate options for the first attack in the sequence hitting or missing: obviously almost all weapon attackers strive to maximise their chance-to-hit, but there's nothing most can do about block.
 
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